ATTACHMENT C - Draft Boulder Approved Tree and Plant List

Regular Meeting, October 16, 2025 · item 5A: Second reading and consideration of a motion to adopt Ordinance 8721 amending Section 4-20-43, “Development Application Fees,” Title 6, “Hea… · 30 pages

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Attachment C - Draft Boulder Approved Tree and Plant List

City of Boulder Tree and Plant List Compiled version – list that includes comprehensive information about each species, including its description, nativity, landscape use, flammability, wildlife interactions, and culture. The list also provides information about beneficial services from each plant species. Simplified version – streamlined list with basic cultural information, wildlife interactions, whether it is a Boulder County native, and whether it can be grown in Restricted WUI zones in the City of Boulder Plant Categories Perennials – list of hardy, broad-leaved, herbaceous plants that live more than 2 years in the Boulder area Shrubs – list of multi-stemmed woody plant species; some species can also be grown as trees and are also included on the tree list Grasses – list of grass species hardy in Boulder area, including species selected for erosion control, groundcover, and ornamental uses Prohibited plants – list of plants not allowed to be included in new developed landscapes, either because of their invasive potential or fire risk Trees – list of trees approved by City of Boulder Forestry Department Site Categories Permitted in Regulated WUI HIZ 5-30 ft – The species marked Y in this column have been documented as having Fire Resistance Scores of 7 or above. These species have documented fire resistance scores of 7 or above and are appropriate for landscapes beyond 5 feet surrounding homes in the designated WUI areas. Please note that these species may vary in fire resistance according to how they are irrigated and maintained. Designated wetland – The species marked as Y in this column are native to Boulder County and are also appropriate to use in natural or constructed wetlands and riparian areas. Boulder County Native – The species marked as Y in this column have been documented by Boulder OSMP as indigenous to Boulder County. These species should be prioritized in properties adjacent to natural areas.

Context Zones Residential

Plantings in areas dominated by buildings exclusively designed for human habitation.

• • •

Low-moderate disturbance Opportunities to conserve water Structural complexity high

Attachment C - Draft Boulder Approved Tree and Plant List

• Parks

Plantings in areas set aside for gathering or recreation

• • • •

Urban

Plantings in high-density areas dominated by hardscape including streetscape, commercial and industrial zones

Agricultural buffers

Plantings adjacent to land designated for producing crops or grazing

Urban agriculture and food production

Planting areas for urban agriculture and food production of annual crops shall be identified on plans. Planting plans for these areas are not required. For perennial crops, identify fruit trees and perennial crops on planting plans and submit documentation for review of the chosen varieties.

• • • • • • • • • • • •

Maintenance regimes variable Low-moderate disturbance Opportunities to conserve water Structural complexity varies Maintenance regimes moderate High disturbance Opportunities to conserve water Low structural complexity Maintenance regimes low High disturbance Water availability variable Maintenance regimes low May be adjacent to natural areas High disturbance High water Maintenance regimes high Often residential or community garden

Outside of the 0-foot to 5-foot noncombustible zone, planting areas for urban agriculture and annual crops are allowed if maintained to reduce dead material and not to exceed 3 feet in height. Fruit trees for food production are prohibited on properties west of Broadway Avenue to protect wildlife by reducing the incidence of encounters with bears in urban areas. Native plantings

Seeding Requirements

Plantings managed to maximize habitat for native plants and wildlife but may also be located in areas of high risk of flooding or fire

• • • •

Low disturbance Water availability variable High structural complexity Maintenance regimes low

Attachment C - Draft Boulder Approved Tree and Plant List

Use only plants that are from a northern seed source and have been grown in nurseries located in hardiness Zones 1 through 5, as shown on a United States Department of Agriculture map, for at least two full growing seasons for trees and larger woody plants, and the entire nursery cycle for herbaceous perennials and grasses. Growing Requirements Exposure Full sun - 6 or more hours of direct sunlight per day Part sun - 4 to 6 hours of direct sunlight per day, including afternoon sunlight Part shade - 4 to 6 hours of sun exposure per day, with most of that in the morning Shade - Less than 4 hours of sun exposure per day, usually in morning or late afternoon or in dappled sunlight under trees Moisture The city plant list includes a water needs category for each plant, that reflects the range of irrigation requirements that the plant will thrive in. The lowest value indicates the lowest amount of water the plant needs to thrive. Each of the values in the list, Very Low, Low, Medium, High, and Cool Season Turf Grass, corresponds to a Plant Factor for use in irrigation design. A Plant Factor represents the relative water demand of the plant when compared to a reference crop of alfalfa. For example, alfalfa has a plant factor of 1.0, whereas Kentucky bluegrass has a plant factor of 0.9, and Desert Four O'Clock (Mirabilis multiflora) has a plant factor of 0.1. The lower the plant factor, the less water the plant requires. Very Low Low Medium High Cool Season Turf Grass

.1 .4 .65 ..8 .9

Minimum Planting Size Many factors are considered when determining the appropriate planting size for a perennial, shrub, or grass. Smaller planting sizes cost less and often transplant more easily. Larger planting sizes may achieve the intended aesthetic effect more quickly and successfully compete with weeds. The listed plant sizes are the smallest planting sizes that will promote design objectives within the first or second year of establishment. F32 F15 #1 #2

2.5” pots 4” pots Between .7-1.1 gallons Between 1.4-2.1 gallons

Attachment C - Draft Boulder Approved Tree and Plant List

#5 Seed

Between 3.4-5.4 gallons Plants usually planted by seed or included in seed mixes

Attachment C - Draft Boulder Approved Tree and Plant List

Scientific Name

Common Name

Cultivars Accepted

Approved for Regulated WUI Areas IR1, IR2 and Water Use IR3 in HIZ 5'-30' (hydrozon e) (Yes/No) Exposure

Maintenance/ pests/ abiotic issues Soil

Height (ft) Spread (ft)

Flowers

Biodiversity and Wildlife Boulder County Native

Minimum Planting Size

Perennials

Achillea lanulosa

Western yarrow

Achillea millefolium

Common yarrow

Adenolinum lewisii

Blue flax

Agastache cana

Hummingbird mint

Agastache foeniculum

High-low

Full sun part sun

Dry to medium, well drained sandy loam soil

1-3'

1.5'

High-low

Dry to medium, well Full sun - drained sandy loam part shade soil

1-3'

1.5'

Hyssop

Ajuga reptans

Bugleweed

Allium cernuum

Nodding onion

Amsonia jonesii

Jones' bluestar

Low

Rocky dry soil, well drained

3’

2’

Full sun - Moist, sandy well part shade drained soils

1.5'

Full sun

Moderate

Moderatelow Full sun

All cultivars

Full sun - Well-drained, part shade organically rich

Moderate

Moderatelow Full sun

Moist alkaline soil, humus rich, high CaCO3 tolerance

Moderatelow Full sun

Sandy, clay, loam

Low

Full sun

Dry, sandy or gravelly 2' soil Stony, calcareous soils, moist soils Well drained soil, sandy

0.5'

1.5'

Full sun - Well drained sandy, part shade rocky soil

Moderate

Sun - part shade

Moist rocky soils

Very low

Full sun

1.5'

Full sun

Poor, dry soil Dry, well-drained, poor soil

1.5'-3'

High

Full sun

Rich, wet, muddy soil; can tolerate drought 1' and clay soil

HighModerate

Full sun

Low

Full sun

Coarse, medium or 4' fine soil Moist to dry soil with good drainage, sandy 1-2' or rocky soil

High-low

Full sun

Dry soil, adaptable

1-3’

Adaptable, neutral alkaline

White; Aug - Sep

Loam, sand, alkaline, 6" neutral

Purple; Apr - Jun

Windflower

Antennaria parvifolia

Small-leaf pussytoes

Low

Full sun full shade Full sun part sun

Aquilegia chrysantha

Golden columbine

Moderate

Aquilegia coerulea

Blue columbine

Artemisia frigida

Fringed sage

Artemisia ludoviciana

Prairie sage

Very low

Asclepias incarnata

Swamp milkweed

Asclepias speciosa

Showy milkweed

Asclepias tuberosa

Butterfly milkweed

Aster (Symphyotrichum) laevis var. geyeri

Smooth blue aster

Moderate

Aster (Symphyotrichum) porteri

Porter's aster

Moderatelow Full sun

Aubrieta deltoidea

Purple rockcress

Low

Baptisia australis

Blue false indigo

Berlandiera lyrata

Chocolate flower

Moderate Full sun ModerateFull sun low

Calylophus serrulatus

Plains yellow primrose

Campanula rotundifolia

Centranthus ruber

Ceratostigma plumbaginoides

Common harebell

Jupiter's beard

Plumbago

Clematis scottii

Scott's sugarbowl

Coreopsis verticillata

Threadleaf coreopsis

C. ruber cultivars, C. ruber 'Albus'

Blue; May- cut down dried foliage in garden Y Jul Pink/orang Cut back in late e/purple/r spring once new ed; Jul growth emerges; N Re-seeds, Blue; Jul - deadhead to promote bloom N Sep Pink/orang Cut back in late e/purple/r spring once new growth emerges; ed; Jul tolerates drought N Oct Divide plants if Blue; May overcrowded N Jun Divide plants Pink/ purple; Jun every third year Y Cut back in late Blue; May - spring once new Jun growth emerges Low maintenance; White; Jun - can be divided in Y Oct the spring White, Can be divided in pink, the spring reddish; White; Jun - Low maintenance Y Aug Deadhead; will Yellow; Apr self seed - Jul Deadhead after White and bloom blue; Apr Jul Do not overwater Yellow; Jun Y Aug Yellow; JulY Oct Can cut old stems down in Pink; Jun late spring if Y Oct necessary; Can cut back if Pink; Maytoo leggy or Y Jun fl t Requires good Orange; drainage, May-Sep produces flowers Blue/ lavender; Cut back in late Aug - Sep spring once new Y

Pearly everlasting

Poppy mallow

2’

Anemone multifida

Callirhoe involucrata

Well-drained, dry. Heavy clay may lead to winter rot. Gravel mulch recommended. 3’

Y Deadhead Color varies; Jun regularly to prolong flowering; N Sep Sep

Collect seeds,

Sandy, dry soil; Does not live as long in clay 1.5-3' soils

Moderatelow Full sun

All cultivars

Anise hyssop

Agastache rupestris

Anaphalis margaritaceae

All cultivars

Easily re-seeds; benefits from White; Jun - division yearly

Well-drained clays, acidic or neutral Slightly alkaline, sandy, gravely

Moderate- Full sun low part shade Well drained soil

3' 2'

1-1.5'

1.5'

Yellow; Jun Aug

1-2'

Well drained alkaline soil, clay, loam, sandy 2-3'

1.5'

Low

Full sun - Well drained soil, part shade medium moisture

Moderate

Slightly alkaline, Full sun - infertile, average to part shade sandy

1.5-3'

1-2'

Moderate

Moderatelow Full sun

Adaptable

Low maintenance

Full sun

Full sun - Adaptable except for part shade poor drainage Full sun - Rich, moist well part sun drained soils

Cut back in late Blue; May- spring once new Jun foliage emerges Yellow; May self-seed; May - Oct low maintenance Low maintenance Red-violet; once established May-Jun Cut back in late Yellow; Apr spring once new Jun foliage emerges Y Self-seeds, deadhead spent Light blue; flowers Y Jun -Sep Pink-red (C. ruber 'Albus' is white; MayAug May benefit from light winter mulch Light blue; in cooler areas Jun -Sep Blue/purpl Hard pruning in e; May-July spring

Low

Moderate

Full sun

-Oct

2-3'

Drought tolerant

Dalea purpurea

Purple prairie clover

Low

Full sun

Delosperma spp.

Hardy iceplant

Low

Full sun

Dry to moist well drained soil Average - lean soils, well-drained

Delphinium nuttallianum

Twolobe larkspur

Low

Full sun part sun

Dry, well-drained soil 2-3'

1-2'

Purple; JunY Sep Varies; Jun- Heat and drought Sep tolerant Sow seeds in fall Blue; May - for cold weather Y Jul stratification

Bees, wasps, flies, butterflies, beetles; nectar for predators/ parasitoids; host for white-lined sphinx, wavy emerald and other

F32

Bees, wasps, flies, butterflies, beetles; nectar for predators/ parasitoids; seeds for chickadees,

F32 Host plant for fritillary butterflies; pollen and nectar for other pollinators; seeds for cardinals, chickadees, F32 Long-tongued pollinators such as hummingbirds and butterflies; F15 deer/rabbit resistant Pollen and nectar for butterflies and bees, esp. bumble bees. nectar for hummingbirds; deer/rabbit resistant F15 Long-tongued pollinators such as hummingbirds and butterflies; deer/rabbit resistant F15 Nectar and pollen for pollinators, esp bees; deer/rabbit resistant Bulbs eaten by squirrels, bears, deer, elk. attracts hairstreak butterfly; special value to native bees,

F32

Nectar and pollen for many pollinators F15 Nectar and pollen source for bees, butterflies and other insects. Host for painted lady butterflies

F32

Attracts hummingbirds F32 Host for painted lady butterflies, F32 nectar for small pollinators Pollen and nectar for long-tongued pollinators: hummingbirds, butterflies, F32 bumblebees and moths Pollen and nectar for long-tongued pollinators: hummingbirds, butterflies, bumblebees and moths; deer/rabbit F32 resistant Pollen and nectar for native bees and flies; host for checkerspot butterflies; F32 i f i b i b Nesting for native bees; deer/rabbit F32 resistant Host plant for monarch butterflies; pollen and nectar for other pollinators; deer/rabbit resistant #1 Host plant for monarch butterfly and gives nectar to variety of pollinators #1 h h i bi d d Flowers nectar source for butterflies, bees and hummingbirds. host for monarchs (not as attractive host as #1 Host for painted ladies; pollen and nectar for many pollinators (bees, F32 Host for painted ladies and pearly crescentspot; pollen and nectar for many pollinators (bees, flies, Forage for pollinators including bees, butterflies, and hummingbirds; deer/rabbit resistant Forage for pollinators including bees, butterflies, and hummingbirds

F32 F32

Forage for many pollinators F32 Host plant for fritillary butterflies; flowers attract bees and other pollinators Forage for bees and butterflies

F32

F32 Nectar and pollen for bees, especially bumble bees, as well as hummingbirds; insects for warblers, F32 sparrows, vireos Forage for generalist bees and butterflies

F32 Late season forage for pollinators

F32 Attracts bees and bumble bees F32 Forage for many small pollinators; seeds for goldfinches, sparrows, towhees, guntings; deer/rabbit F32 resistant Host plant for sulfur butterflies; pollen and nectar for many pollinators. Special value to solitary bees, bumble bees, honey bees. Birds eat seeds; F32 deer/rabbit resistant Forage for honey bees F32 Forage for long-tongued pollinators such as hummingbirds, butterflies, F32 and bumble bees

Attachment C - Draft Boulder Approved Tree and Plant List

Digitalis obscura

Echinacea angustifolia

Echinacea purpurea

Engelmannia peristenia

Epilobium canum ssp. garrettii

Erigeron speciosus

Eriogonum umbellatum

Erysimum capitatum

Sunset foxglove

Moderate- Full sun low part shade Well-drained soil

Narrow-leaved purple coneflower

Moderate- Full sun - Clay, loam, sandy, low part shade neutral, dry

Moderate- Full sun low part sun

Eastern purple coneflower

Engelmann's Daisy

Creeping hummingbird trumpet

Low

Aspen daisy/ Aspen fleabne

Sulphur buckwheat

Western wallflower

Low

Full sun

Well-drained, sandy or rich soils

Clay, loam, sandy

Full sun part shade Clay, loam, sandy

Fertile well drained soils

3’

1.5'

2.5'

18”

Low

Full sun

Very low

Full sun - Good drainage, part shade sandy, gravelly soil

1-2'

Low

Full sun - Moist well drained part shade soil

1-2'

Fertile, moist soils but will tolerate clay.

4-6'

Sand, loam, clay

2-4'

2-6'

Eutrochium purpureum var. purpureum

Joe Pye weed

Moderate

Full sun shade

Eupatorium serotinum

White boneset

Moderate

Full sun

Gaillardia aristata

Blanket flower

Moderate- Full sunlow part shade Well drained soil

Geranium caespitosum var. caespitosum

Wild geranium

Moderate

Full sunWell drained soil, part shade rocky

1’

Cranesbill

Geranium richardsonii

Richardson's geranium

Geranium viscosissimum

Sticky geranium

Moderate HighModerate Moderatelow

Part sun 1.5' part shade Well-drained Full sun - Prefers loamy or clay 1' part shade soils Full sun 3' part shade Well drained soil

Geum triflorum

Prairie smoke

Moderate

Full sun

Dry, moist rich prairie loams, clay and sand 1.5'

Glandularia bipinnatifida

Wild verbena

Low

Full sun

Well drained soil

1'-1.5'

HighModerate

Full sun

Medium to wet soil, rich

Low

Full sun

Dry, alkaline, rocky, well-drained

Geranium 'Johnson Blue' and other hybrids

Helenium autumnale

Helianthemum grandiflorum ssp. grandiflorum

Autumn sneezeweed

Rockrose

2.5' 1' 3'

Helianthus maximiliani

Maximillian sunflower

Moderatelow Full sun

Average dry to medium well drained 6' soil

Helianthus nuttallii

Nuttall's sunflower

Moderatelow Full sun

Well-draining moist, tolerant of sand and clay

Helianthus pumilus

Small sunflower

Heliomeris multiflora

Showy goldeneye

Helleborus orientalis

Lenten rose

Low

Full sun 4' part shade Dry, rocky soil Average, dry to medium well drained Full sun 4' soil

Moderate

Part sun - Rich, humusy, wellpart shade drained; rocky ok

1.5'

Low

1.5'

Orange; May-Jun

Pink; Jul Sep Pinkpurple; JunAug

Yellow; May - Sep

Red; Jul Oct

Can be cut back in midsummer to prolong bloom; cut back in late spring once new foliage emerges Cut back in late spring once new foliage emerges; drought tolerant Low maintenance

Attracts bumble bees

Low maintenance; can shear back in spring; weed any extra seedlings

Forage for solitary bees, flies, butterflies; deer/rabbit resistant

Low maintenance - can be trimmed to promote lateral growth or divided if clump gets too large

Nectar and pollen for bumblebees; nectar for butterflies, hummingbirds and hawkmoths; deer/rabbit resistant

F32 Seeds for birds; nectar and pollen for bees, wasps, flies, butterflies F32 Seeds for birds; nectar and pollen for bees, wasps, flies, butterflies

F32

F32 Deadhead to Pollen and nectar for small pollinators, encourage bees and butterflies; deer/rabbit extended bloom resistant and cut back after flowering to Lavender; rejuvenate Y F32 Jun-Oct foliage. Low maintenance Host for blues, forage for native bees, Yellow; parasitoid insects, butterflies; Aug-Oct Y F32 deer/rabbit resistant Cut back spent Larval host for Sara orangetips, pale Gold/ flowers swallowtails, and duskywings, orange; provides nectar for many bees and May-Jul Y F32 butterflies; birds eat seeds Cut back old Forage for bees and butterflies Pinkgrowth in late Purple; Jul- spring once new #1 Aug growth emerges Cut back old Attracts bees, moths, skippers, growth in late beetles, flies, and butterflies; special White; Aug- spring once new value to native bees; deer/rabbit F15 Oct growth emerges resistant Cut back if Pollen and nectar for many pollinators, flowering association with Schinia flame moth; declines in the seeds/ insects for sparrows, finches, summer; grosbeaks, buntings, chickadees; deadhead to deer/rabbit resistant Gold/ red; promote ongoing Y F32 May-Sep bloom PinkPollen and nectar for bees and flies Low maintenance Purple; May - Oct Y F32 BlueLow maintenance Forage for generalist bees and purple; Junbutterflies; deer/rabbit resistant F32 Sep White/pink Low maintenance Attracts butterflies Y F32 ; June-Aug Pink; May- Low maintenance Pollen and nectar for bees, butterflies Y F32 Jul and flies Low maintenance Pollen and nectar for bumblebees, - trim back in attracts butterflies; deer/rabbit Reddish spring once new resistant pink to growth emerges if purple; desired April-June F32 Pinkish - Low maintenance Nectar and pollen for butterflies and purple; Junother pollinators. Rabbits eat foliage, Y F32 Sep birds eat seeds Cut back in June Host plant for eight different to increase butterflies, including the painted lady; nectar and pollen for many pollinators, branching; avoid especially butterflies and bees; overfertilizing; special value to native bees deadhead to H. autumnale encourage var. bloom; divide montanum is clumps as native to Yellow; Jul- needed to Boulder County F32 Oct maintain vigor Shear plant after Forage for generalist pollinators bloom for attractive shape; winter mulch promotes survival - esp. evergreen Yellow; boughs May - Jun F32 Cut down by half Late bloomer; host plant for painted lady butterflies; late bloomer in mid-summer to manage size; important for many pollinators; Yellow; may re-seed in shelter; seeds for birds Aug-Sep #1 irrigated gardens Nectar and pollen for many pollinators, including specialist bees; special value to native bees; host for Milbert's tortoiseshell and other leps, seeds for Yellow; Julbirds and small mammals; deer/rabbit Y #1 Oct resistant Host plant for painted lady butterflies; late bloomer - important for many pollinators including specialist bees; Yellow; Julshelter; seeds for birds Y F15 Aug Nectar and pollen for bees and Yellow; Julbutterflies Y F15 Oct White to Nectar and pollen for early bees; pink deer/rabbit resistant shades; Apr F32

Attachment C - Draft Boulder Approved Tree and Plant List

Hemerocallis spp. and cultivars

Heterotheca villosa

Daylilies

Hairy false goldenaster

Heuchera spp.

Coral bells

Ipomopsis aggregata

Scarlet gilia

Moderatelow Full sun

Adaptable

Low

Full sunSandy, dry well part shade drained soils

Moderate

Full sun

Low

Full sun

1'-2'

humusy, welldrained; avoid heavy clay but rocks are ok 1.5 Sandy, loam, igneous 3-6' soil, dry

1-2'

High

Full sun

Low

Full sun

Medium to wet fertile, slightly acidic well 1-2' drained soils Humusy, well-drained 2' dry

English lavender

Low

Full sun

Alkaline, well-drained 1.5'

1.5'

Liatris ligulistylus

Meadow gayfeather

Moderate

Full sun

Adaptable, but does not like wet winter soil

Liatris punctata

Dotted gayfeather

Liatris pycnostachya

Prairie gayfeather

Lupinus argenteus

Silvery lupine

Mimulus guttatus

Seep monkeyflower

High

Full sun Full sun part sun

Mimulus lewisii

Purple monkeyflower

High

Mirabilis multiflora

Desert four o'clock

Monarda fistulosa

Wild bergamot

Iris missouriensis

Rocky Mtn Iris

Kniphofia uvaria

Red hot poker

Lavandula angustifolia

Moderate- Full sun - Dry to moist well low part shade drained soil

Moderate

Low

Acidic, moist, poor, Full sun - well-drained, rocky or 5' part shade sandy loam

Sandy/rocky dry to moist well drained soils

1-3'

1.5'

Full sun

Moist Fertile, humus rich, moist soil

1.5'

Very low

Full sun

Excellent drainage

Low

Full sun

Dry to medium moist well drained soil

2-4'

2-3'

Oenothera caespitosa

White evening primrose

Very low

Full sun

Good drainage, clay soils

0.5-1'

1.5'

Oenothera howardii

Stemless evening primrose

Very low

Full sun

Rocky or sandy loam

Oenothera macrocarpa

Evening primrose

Moderatelow Full sun

Rocky gravelly, sandy 0.5' soils

1.5'

Penstemon barbatus

Beard-lip penstemon

Low

Full sun

Fertile, dry to moisture soil, well drained, rocky soil

2-4'

Mat penstemon

Moderatelow Full sun

Dry, well-drained, sandy or rocky

6”

Firecracker penstemon

Very low

Full sun

Rocky, sandy soil

1.5'

Penstemon caespitosus Penstemon eatonii

Penstemon grandiflorus

Large beardtongue

Low

Full sun

Sandy, well-drained

1.5'

Penstemon linariodes v. coloradoensis 'P014S'

Blue-mat penstemon

Low

Full sun

Sandy, loam

.5'

Penstemon pinifolius

Pine-leaf penstemon

Low

Full sun

Clay, loam, sandy

1.5'

Nectar for butterflies; deer/rabbit resistant

Gold to red shades; May-Sep

Yellow; MayOctober

#1 Easily re-seeds, easy to establish, drought tolerant. deadhead to promote longer blooms, cut down after hard frost

Host plant for painted lady butterflies; pollen and nectar for many pollinators including butterflies, flies, bees; important for specialist bees; seeds for birds

Y F32 Winter mulch in Nectar for hummingbirds cold climates recommended; divide every 3-4 years; deadhead Pink-red; to encourage H. parviflora F32 May - Jun bloom Red; AugI. aggreggata Nectar for hummingbirds; deer/rabbit ssp. candida resistant F32 Oct Remove dying Early bloom - nectar and pollen for foliage in fall bees; aquatic shelter. Attracts Lavender; butterflies; nectar for hummingbirds; Y #1 May-Jun deer/rabbit resistant Orange; Deadhead after Forage for hummingbirds and bees; #1 May-Jun bloom deer/rabbit resistant Purple; May rot in heavy Forage for honey bees and other F32 May - Jul soils over winter generalists; deer/rabbit resistant Low maintenance Pollen and nectar for many pollinators, - trim back in especially butterflies spring once new Pinkgrowth emerges if purple; Jul- desired #1 Sep Low maintenance Pollen and nectar for many pollinators, - trim back in especially butterflies; seeds for spring once new sparrows, vireos, waxwings, orioles growth emerges if Pink; Jul- desired Sep Y #1 Low maintenance Pollen and nectar for many pollinators, - trim back in especially butterflies; seeds for birds spring once new Pinkgrowth emerges if purple; Jul- desired #1 Sep Low maintenance Attracts birds, butterflies and - trim back in hummingbirds, and especially bumble bees. Special value to native bees. spring once new growth emerges if Host plant for sulfur butterflies and Blue/purpl desired some blues; seeds for grosbeaks, e; Junevireos, woodpeckers, jays; deer/rabbit July Y #1 resistant Yellow; Apr Nectar and pollen for bees, esp F32 Aug bumble bees; aquatic shelter Rose pink; Cut back after Nectar and pollen for hummingbirds, F32 Jun-Sep flowering bees, esp bumble bees PurpleDon't overwater; Forage for long-tongued bees, pink; Jun- can be mowed in butterflies, moths, hummingbirds; Sep F32 October deer/rabbit resistant Provide good air Nectar and pollen for bumblebees; circulation, nectar for butterflies, hummingbirds deadhead spent and hawkmoths; deer/rabbit resistant Pink; May- flowers, divide Y F32 Sep every 3 years Don't overwater Host plant for sphinx moth; nectar and White; Aprpollen for wide range of pollinators Y Aug F32 Don't overwater Host plant for sphinx moth; nectar and pollen for wide range of pollinators; food and shelter for grassland and Yellow; shrubland birds; deer/rabbit resistant May-Jul Y F32 Low Host plant for sphinx moth; nectar and maintenance; pollen for wide range of pollinators. allow to go to Attracts hummingbirds seed and then weed any undesirable seedlings; trim back in spring once new growth Yellow; Apr emerges if F32 Aug desired Do not Nectar and pollen for long-tongued overfertilize or pollinators such as bumblebees and overwater. Low hummingbirds; special value to native maintenance. bees; deer/rabbit resistant Deadhead after bloom for appearance and Red; Jun- to encourage Oct F32 additiional bloom Low Pollen and nectar for long-tongued maintenance. pollinators; deer/rabbit resistant Deadhead after bloom for appearance and Lavender; to encourage F32 June additiional bloom Red; May- Short-lived Pollen and nectar for long-tongued F32 Jun pollinators; deer/rabbit resistant hand trim back Pollen and nectar for long-tongued pollinators, especially bumble bees; dead stems after Lavender; blooming if special value to native bees; F32 May-Jun desired deer/rabbit resistant Doesn't do well in Pollen and nectar for long-tongued frequently pollinators, especially bumble bees; irrigated areas; deer/rabbit resistant hand trim back Blue; May - dead stems in F32 Jun spring Hand trim Pollen and nectar for long-tongued flowering stalks pollinators, especially bumble bees; Red; May- post bloom if special value to native bees; Jul F32 desired deer/rabbit resistant

Attachment C - Draft Boulder Approved Tree and Plant List

Penstemon pseudospectabilis

Penstemon secundiflorus

Penstemon strictus

Penstemon virens

Penstemon whippleanus

Phacelia sericea

Desert beardtongue

Sidebells beardtongue

Rocky Mtn. Beardtongue

Blue mist beardtongue

Whipple's penstemon

Silky phacelia

Low

Full sun

Dry, well-drained soils

Low

Full sun part sun

Fertile, dry to moisture soil, well drained, rocky soil

Part sun

Tolerates heavy soils and moisture, but prefers dry well drained soils. Sandy 2' soils

Low

Full sun

Sandy, rocky well drained soils

Moderate

Full-part sun

Clay, rocky, adaptable

Moderate

Full-part sun

Rocky dry soil, low CaCO3 tolerance

Low

2.5'

Magenta; May - Aug

Blue/violet ; May-Jul

Blue/purpl e; May-Jun

Blue/purpl e; Mar-Aug

Rose pink; Jun-Sep

1-2'

2-4'

Blue/purpl e; May-Aug

Phlomis cashmeriana

Cashmere sage

Low

Part shade Clay, loam, sandy

2';

Phlox bifida

Snowmass phlox

Moderate

Full sun to part shade Clay, loam, sandy

18"

Phlox subulata

Moss phlox

Polemonium caeruleum

Jacob's Ladder

Polystichum munitum

Western sword fern

Potentilla rivalis Pulsatilla patens ssp. multifida

Ratibida columnifera

Brook cinquefoil American pasqueflower

Prairie coneflower

Moderate

Full sun

Humusy, welldrained, sandy or gravelly

.5'

1.5'

Moderate Moderate to high

Full sun Full - part sun Full - part sun

Rich, well-drained Adaptable but welldrained Fertile soil, good drainage

Low

Full sun

Well drained soils, dry 1.5'

Full sun

Dry to medium well drained soils, usually 1-3' calcareous soils

1-1.5'

Moderate

Low

Y Deadhead to promote continued flowering

1-2'

Hand trim flowering stalks post bloom if desired

1.5'

2-4'

Low maintenance - leaving the flower stalks to dry provides Pink; May- seasonal interest Jun White-pale Low maintenance blue; AprJun Cut back stems after flowering by 1/2 to promote Pink denser growth lavender; may get a 2nd Apr-Jun bloom Cut back to base after bloom; may self-seed in irrigated gardens; may scorch if too Bluemuch sun and purple; Apr- decline during the Jun hot summer

Rudbeckia laciniata

Salvia azurea var. grandiflora

Salvia greggii 'Furman's Red' or 'Wild Thing'

Salvia officinalis

Sedum spp.

Black-eyed Susan

Green-headed coneflower

Pitcher sage

Full sun

Acidic, well-drained

Low

Full sun

Moist, slightly acidic

Low

Furman's Red sage

Low

Common sage

Stonecrop

Moderate

Low

Sun/ part shade

Full sun

Dry, well-drained soil 4'

Rocky, well-drained soil

1-2'

6”

Lanceleaf stonecrop

Very low

Full sun

Sempervivum tectorum

Hens and chicks

Moderatelow Full sun

Sandy, gravelly soils

Moderate

Clay, loam, sandy

Sedum lanceolatum

Goldenrod

Full sun

Rocky, well-drained soil

Solidago canadensis

Full sun

Sandy, loamy, clay

Gold; JulOct

F32

Forage for long-tongued pollinators such as moths

F32 Forage for bees and other pollinators; deer/rabbit resistant

Y Can be shortlived

Rudbeckia hirta

F32

F32 Nectar and pollen for bumblebees; nectar for hummingbirds; special value to native bees; deer/rabbit F32 resistant Nectar and pollen for bumblebees; nectar for hummingbirds; special value to native bees; deer/rabbit F32 resistant Attracts bees, flies, butterflies and hummingbirds; special value to native F32 bees Forage for bumble bees; deer/rabbit resistant

Forage for long-tongued pollinators such as moths and butterflies

N/A Yellow; June-Aug Lavender; Easy to start from Y Apr-Jun seed Drought tolerant Red and yellow; JunSep

Pollen and nectar for long-tongued pollinators, especially bumble bees and hummingbirds; special value to native bees; deer/rabbit resistant Nectar and pollen for bumblebees; nectar for hummingbirds; special value to native bees; deer/rabbit resistant Nectar and pollen for bumblebees; nectar for hummingbirds; special value to native bees; deer/rabbit resistant

Y Divide clumps to control growth; wait until late spring or early summer to remove last year's stems, Gold; Jul- whenever Oct possible Too much fertilizer or water makes the plant floppy; can be mowed periodically; tolerates heat, Blue; Jul- drought and Oct flooding Becomes brittle with too much moisture; hand Red; May- trim stems in late Sep spring if needed Can be hardtrimmed if it starts to sprawl; deadheading Lavender; after bloom Jun recommended Low maintenance; may remove last year's flowering stems in late spring or early Pink; Jul- summer if Sep desired Low maintenance Yellow; JulAug Low maintenance; individual Reddish rosettes die after purple; Jun- bloom and can be Jul removed Cut down old stems in late spring or summer Yellow; if desired Aug-Nov Y

F32 Shelter; deer/rabbit resistant F32 Nectar and pollen for bees; aquatic F32 shelter Nectar and pollen for bees and F32 butterflies, nectar for hummingbirds Attracts sweat bees, flies, small butterflies. birds such as sparrows, finches, grosbeaks, buntings, chickadeeseat seeds, deer will eat F32 flower; deer/rabbit resistant Forage for small pollinators, including bees, butterflies, flies, wasps and others; seeds for birds; insects for waxwings, orioles, nuthatches, warblers, wrens, thrushes, jauys, chickadees; host for gorgone F32 checkerspot Pollen and nectar for many pollinators, including specialist bees, wasps, butterflies; special value to native bees; seeds for birds

#1 Late season forage for bumble bees, butterflies, hummingbirds; special value to native bees; deer/rabbit resistant

F32 Forage for hummingbirds, butterflies, bumble bees

F32 Forage for generalist bees and butterflies; deer/rabbit resistant

F32 Host for fritillary butterflies; pollen and nectar for bees, flies, butterflies and wasps; deer/rabbit resistant

F32 Host for fritillary butterflies; pollen and nectar for bees, flies, butterflies and F32 wasps Deer/rabbit resistant

F32 Late forage for bees, flies, beetles and other pollinators; seeds for birds; insects for finches, sparrows, buntings, grouse; deer/rabbit resistant

F32

Attachment C - Draft Boulder Approved Tree and Plant List Solidago sphacelata 'Golden Fleece'

Sphaeralcea coccinea

Sphaeralcea munroana

Stachys byzantina and cultivars

Dwarf goldenrod

Scarlet globemallow

Munro's globemallow

Moderatelow Full sun

Low

Lamb's ear

Poor, well-drained 2' Thrives in dry, poor limestone soils, Full suntolerates variety. dry, 1' part shade well-drained soil

Dry, rocky soil

Not too rich, welldrained

1.5'

Well-drained

Yellow; May-Jun

White; AugOct

Yellow; May

Pink; JunJul

Low

Full sun

Low

Symphyotrichum ericoides

White heath aster

Moderate- Full sunlow part shade Dry, adaptable

Thymus serpyllum

Creeping thyme

Tradescantia occidentalis

Spiderwort

Verbena hastata

Blue vervain

Veronica 'Reavis'

Crystal River veronica

Zinnia grandiflora

Plains zinnia

Orange; Apr-Sep

Moderate- Full sunlow full shade

Prince's plume

Spreading golden banner

Yellow; Aug-Sep

Orange; May-Jun Purplishpink; MayJul

Stanleya pinnata

Thermopsis divaricarpa

HighModerate

Full sun

Low

Full sun

Clay, sandy, loam 2' Sandy, gritty, or rocky well-drained soils; .25' dislikes moist soils

Low

Full sunfull shade

Fertile, moist well drained soils

HighModerate Moderatelow Low

Full sun

Full sun3' part shade Moist Full sun3" part shade Clay, loam, sandy Full sun to part shade Well drained dry soils 0.5-1'

2' 2' 0.5-1'

Deadhead to encourage bloom Drought tolerant reseeds easily, cut back after flowering

Attracts bees, flies, beetles and other pollinators

Supplemental moisture will Y prolong bloom Low maintenance -

Remove old growth in late winter to make space for spring growth if desired Y Low maintenance -

F32 Host plant for fritillary butterflies; flowers attract bees and other pollinators; special value to native F32 bees Host plant for common checkered skipper; flowers attract bees and other pollinators; special value to native F32 bees "Wool" for leafcutter bees; visited by honey bees and bumble bees; F32 deer/rabbit resistant Forage for many pollinators including bees, flies, and butterflies F15 Late season forage for many pollinators, including specialist bees; special value to native bees and F32 biological control insects Pollen and nectar for long-tongued pollinators, especially bumblebees; deer/rabbit resistant F32 Forage for generalist bees F32

Protect young growth from Purple; Jun- slugs, cut back Jul flowered stems Y May self-seed in Purple; Jun- irrigated Y Sep locations Blue; Apr- Low maintenance Jun Yellow; Apr Low maintenance Nov

Nectar and pollen for bees

Do not plant near incense cedar, good fall color. Don't plant with White; Apr- crabapples, Jun pears or junipers Y Prune for shape and health as needed; may spread White; underground May-Jul Y Low maintenance

Birds such as crows, thrushes, robins, and western tanagers eat fruits, pollinated by hummingbirds and butterflies. butterfly host, California hairstreak. Attracts orange tip and #5 elfin butterflies Shelter for birds and other animals, browse and fruit for birds and mammals, spring forage for native bees and flies; special value for native bees; host for swallowtail butterflies #5 Host for silver spotted skipper and gray hairstreak; flowers attract many bees, butterflies, flies, hummingbirds; shelter and browse for mammals #2 Host for silver spotted skipper and gray hairstreak; flowers attract many bees, butterflies, flies, hummingbirds; shelter and browse for mammals #5

F32 Nectar and pollen for butterflies and other pollinators. larval host for the common buckeye Forage for generalist bees

F32 F32

Nectar and pollen for bees; attracts butterflies

F32

Shrubs and vines

Amelanchier alnifolia

Saskatoon serviceberry

Full sunpart sun

Well drained, high CaCO3 tolerance

8-15'

Moderate- Full sunlow part sun

Well-drained rocky soils, sandy, sandy loam, loam, clay loam, clay

6’

Moderate

Amelanchier utahensis

Utah serviceberry

Amorpha canescens

Lead plant

Low

Full sun

Well-drained rocky or 3-6' sandy soils

False indigo

Moderate High Full sun

Moist to dry sands or clay loam, pH 3-15' adaptable

Purple; May-Jul

5-15'

Purple; Apr Jun

Low maintenance

Amorpha fruticosa var. angustifolia

Y Low maintenance

Amorpha nana

Moderate- Full sunpart sun low

Dwarf leadplant

Clay, loam, sandy, gravelly

2-3'

Purple, Jun

Y Prune dead/dying wood, prefers winter shade of pines

Arctostaphylos uva-ursi

Arctostaphylos x coloradensis

Aronia melanocarpa

Atriplex canescens

Campsis radicans

Ceanothus americanus

Ceanothus fendleri

Kinnikinnick

Low

Moderate- Full sunlow part sun

Manzanita

Black chokeberry

Moderate

Four-winged saltbush

Very low

Trumpet creeper

New Jersey tea

Buckbrush/ Mountain lilac

Full sunpart sun

Full sun

Acidic soil (pH<6.8), dry, moist. rocky or sandy soil, excellent drainage

Loam, sandy

Acidic, moist

2’

Alkaline, well-drained soils; saline tolerant 6'-12'

Moderate

Full - part sun

Moderate

Full - part sun

2-3'

Low

Dry, rocky or gravelly Part shade soils

Lean - average soils

25-40'

5’

3-6'

10'

White/ Pink; MarJun

Pink; May

Y Low maintenance - only remove damaged branches in spring

Flood tolerant; prune dead or damaged branches when needed; remove White; Apr- root suckers to Jul manage spread Low maintenance; water sparingly 1st year and then remove irrigation; severe pruning helps with shaping the plant; may Yellow; Apr spread with Oct Y irrigation Prune in late winter or early spring, cutting Red, branches back to orange, 3-4 buds to yellow; Jun- promote compact Sep growth Can withstand drought but has White; Jun- difficulty Aug transplanting Shear for compact growth White; JunJul

Host for silver spotted skipper and gray hairstreak; flowers attract many bees, butterflies, flies, hummingbirds; #1 shelter and browse for mammals Attracts butterflies, bees and hummingbirds. Pollen and nectar for native bees, nectar for hummingbirds, Larval host of Callophyrs polia, C. augustinius, Bolaria freija. Provides fruit for birds such as thrushes, wrens, grouse, waxwings and other wildlife; deer/rabbit resistant #2 Pollen and nectar for native bees; Browsed by wide variety of wildlife

Pollen and nectar for native bees; Browsed by wide variety of wildlife

#2 Shelter and nesting for birds and mammals; forage for small pollinators; seeds for birds and mammals; host for sootywings; good nesting and cover for birds

#5 Nectar for hummingbirds and other long-tongued pollinators; deer/rabbit resistant

#2 Forage for pollinators and biocontrol; special value to native bees; host for duskywings, metalmark butterflies; shelter and nesting for birds and small #2 mammals

Attachment C - Draft Boulder Approved Tree and Plant List

Cercis occidentalis

Chamaebatiaria millefolium

Western redbud

Fernbush

Low

Very low

Adaptable

Full sun

Clay, loam, sandy, gravelly

15'

Full sunClematis spp. and cultivars

Cornus sericea

Moderate part sun

Clematis

6-12'

7-10'

Full sunpart sun Full sun part sun

Poor rocky soil, excellent drainage

6-8'

Loamy well-drained

Well drained

5’

Pink; Jun

Light yellow; May - Jun

Cotinus coggyria 'Royal Purple'

Purple smoke bush

Moderate

Cotoneaster adpressus

Creeping cotoneaster

Low

Cholla

Moderatevery low Full sun

Ericameria nauseosa ssp. nauseosa

Mormon tea

Very low

Dwarf blue rabbitbrush

Low

Moist, well drained soils

High-low

Ephedra viridis

12'

Full sunshade

Red osier

Cylindropuntia spp.

Well-drained

Pruning is minimal; water young trees regularly but Magenta; overwatering can Apr-May lead to root rot Prune lightly in late winter for a bushier shrub, White; Jul- deadhead if Oct desired Provide a sturdy support for climbing; pruning needs depend on flowering time; more flowers will come with regular blossom booster Varies; application May-Sep Prune out 1/4 old and faded stems in early spring to highlight bright color White; May-Oct Y Prune very lightly Yellow; Jun in spring if bloom Aug is desired White; Low maintenance May - Jul Low maintenance

Full sun

Clay, loam, sandy

Clay-alkaline soils, well drained

Yellow; Aug-Oct

Manage spreading rhizomes if needed Remove dead wood as needed

Low

Full sun

Adaptable

12'

Very low

Full sun

Dry

Low

Full sun

Dry, neutral sandy, loam, clay, caliche

Highmoderate

Full sunshade

Moist

6-20'

10-15'

Rock spiraea

Low

Full sun part shade Dry, rocky

White; JunAug

Jamesia americana

Waxflower

Moderate - Full sunlow shade

Loam

White; May-Jun

Krascheninnikovia lanata

Winterfat

Very low

Full sun

Clay, chalky, or sandy 3' alkaline soils,

Moderate

Full sunpart sun

Average, welldrained, organically rich

Tall green rabbitbrush

Low

Full sun

Fallugia paradoxa

Canyon plume

Low

Full sun

Fendlera rupicola

Cliff fendlerbush

Very low

Full sun

Forestiera pubescens

Desert olive

Gutierrezia sarothrae

Broom snakeweed

Hesperaloe parviflora

Red yucca

Holodiscus discolor

Ocean spray

Holodiscus dumosus

Lonicera involucrata

Lonicera periclymenum

Mahonia aquifolium

Mahonia repens

Twinberry

Clay-alkaline soils, well drained

Gravelly, sandy, dry, well-drained soil Dry, rocky, welldrained, poor, alkaline

4-6'

4-5'

3-6'

10'

Moderate

Full sunpart sun

20'

Compact Oregon Grape

Low

Part sun to Well-drained, slightly 6' shade acidic

Creeping Oregon grape

Moderate- Full sun to Moist humus rich low part sun soils, well drained

Woodbine

Humusy, organically rich

Malus sargentii

Sargent crabapple

Moderate

Full sun

Well-drained acidic loams but adaptable

15'

Opuntia macrorhiza

Prickly pear cactus

Very low

Full sun

Dry acidic, rocky or sandy soils

Opuntia polyacantha

Prickly pear cactus

Very low

Full sun

Dry, clay loams or rocky soils

Parthenocissus quinquefolia

Virginia creeper

50'

10'

Full sun - Well-drained; adaptable Moderate shade

#5 Forage for bees, wasps, and flies, especially attractive to bumble bees; cover for urban birds; deer/rabbit resistant

Forage for generalist bees; deer/rabbit resistant

#1 Berries and perches for over 98 spp of birds including flickers, tanagers, woodpeckers and catbirds; , mammals, butterflies and birds. Larval host of the Spring Azure.; deer/rabbit resistant; deer/rabbit resistant Shelter and nesting for birds and mammals; deer/rabbit resistant Cover and protection; forage for generalist bees Pollen and nectar for bees, including specialists, fruit for mammals; winter shelter Cover and protection

#5 #2

Height and spread can be managed with early spring pruning and Yellow; removal of 1/3 old Aug-Oct wood Do not shear - cut oldest woody stems to ground White; Apr- to rejuvenate and Jun remove suckers Pink, Lankiness is white; Apr- improved by Jun pruning Insignifica Prune for size and nt; Aprhealth as needed May do not overwater Yellow; Aug-Nov Y Don't overwater Pink; JunAug Seeds require cold stratification (less than 41 degrees) up to 18 White; weeks May-Aug Y

Ericameria nauseosa

Forage for generalist bees and butterflies, as well as hummingbirds; deer/rabbit resistant

Low maintenance; prune dead wood Y as needed Must have male White; plant nearby to May-Jul Y produce fruits Low maintenance; Yellow; Jun may naturalize to Jul form colonies Crimson Prune after with flowering yellow/whi te centers; Jul-Oct Protect from sun Yellow; Apr and wind May Little pruning required; protect Yellow; Apr from sun and May Y wind Prune in late winter; drought White; tolerant once May - Jun established Low maintenance Yellow; May-Jun Y Low maintenance Yellow; Apr May Y Prune to manage size as needed; Greenish- have a Japanese white; May- beetle mgmt plan Aug

Host plant for checkerspots; late bloomer - important for many pollinators; shelter and nesting for mammals and birds; deer/rabbit resistant Host plant for checkerspots; late bloomer - important for many pollinators; shelter and nesting for mammals and birds; deer/rabbit resistant

#1 Pollen and nectar for many pollinators, especially mid-sized or small bees; deer/rabbit resistant #2 Browse for large mammals; forage for pollinators

Berries for birds; shelter and nesting for birds, mammals, invertebrates; #1 deer/rabbit resistant Late season forage for flies, beetles, and solitary bees; seeds for birds; #1 deer/rabbit resistant Nectar for hummingbirds as well as other long-tongued pollinators; #1 deer/rabbit resistant Host plant for spring azure, swallowtail and Lorquins admiral butterflies. Visited by bees (bumble and sweat); special value to native bees; good shelter for birds

Browse for mammals; forage for many pollinators; cover and protection

Cover and protection; seeds for birds; forage for pollinators

#1 Cover and protection for birds and mammals Birds eat fruits; hummingbirds and butterflies are attracted to tubular flowers

Hummingbirds visit flowers; birds eat berries; shelter; ; deer/rabbit resistant

#1 Early bloom - nectar and pollen for bees; shelter all year; berries for wildlife; deer/rabbit resistant Early bloom - nectar and pollen for bees; shelter all year; berries for wildlife;deer/rabbit resistant

Early forage for honey bees, fruit for birds

#5 Relationship with specialist bees; fruit for birds and small mammals; ; #1 deer/rabbit resistant Pollen and nectar for bees, including specialists, fruit for mammals; winter #1 shelter; ; deer/rabbit resistant Forage for generalist bees and wasps; shelter; host for sphinx moths; berries for birds; ; deer/rabbit resistant #1

Attachment C - Draft Boulder Approved Tree and Plant List

Philadelphus lewisii

Philadelphus microphyllus

Physocarpus monogynus

Physocarpus opulifolius

Potentilla fruticosa

Prunus americana

Prunus pumila var. besseyi

Cheyenne mock orange

Little-leaf mockorange

Low

Moderate

Mountain ninebark

Low

Ninebark

Low

Shrubby cinquefoil

Moderate

Full sun

Clay, loam, sand

Full sun

Well-drained, adaptable, even to shallow rocky or heavy soils

Full sun part sun

Full sunpart sun

Well drained soil

Sand cherry

Moist, well-drained soil

Low

Full sunpart shade Dry, rocky soil

Full sun

Purshia mexicana

Mexican cliffrose

Very low

Purshia tridentata

Antelope bitterbrush

Moderate

Full sun

Dry rocky welldrained soils; Dry rocky welldrained soils;

Low

Full sunpart sun

Well drained soil

Low

Full sunpart sun

Rhus aromatica 'Autumn Amber'

Rhus aromatica 'Gro-Low'

Autumn Amber fragrant sumac

Gro-Low fragrant sumac

Full sunpart sun

Three-leaved sumac

Low

Rhus glabra

Smooth sumac

Moderate- Full sunlow part sun

Ribes aureum

Golden currant

Rhus aromatica var. trilobata

Ribes cereum

Rosa glauca

Wax currant

Low

Redleaf rose

Rosa spp.

Shrub and tea roses

Rosa woodsii

Wood's rose

Rubacer parviflorum

Low

Thimbleberry

All shrub and tea rose cultivars

Full sunpart sun

3’

pH neutral clay, loam 5-8'

Moderate - Full sunRich, well-drained low part shade loams

American plum

Well drained soil

2-4'

15-25'

4-6'

3-5'

15-25'

White; May-Jun

White; AprMay

12-18"

6-10'

Yellowish- Remove dead green; Mar- wood if necessary Apr

6-10'

Adaptable to most dry 15' soils

15'

Moist to drier soils

5-10'

6-10'

3-6'

Full sun

Adaptable but wellModerate drained 4'

Moderate

Full sunpart sun

3-6'

Pink; MayJul

High

Full sunpart sun

3-5'

White; May-Aug

Rubus deliciosus

Boulder raspberry

Moderate- Full sunlow part sun

Salix exigua

Sandbar willow

High

Full sun

Rocky soils

3-6'

1.5-5'

Clay, loam, sand well 3-5' drained soil Wet gravelly sandy 4-15' soils

5-6' 15-20'

#2 Shelter for birds and other small animals; small flowers for native pollinators; special value to native bees

White; May-Aug Yellow/whi te; Apr-Jun

#2 Shelter for birds and other small animals; small flowers for native pollinators; special value to native bees

#2 Forage for butterflies, flies, and bees;deer/rabbit resistant

#1 Early season forage for butterflies, flies, and bees; special value to native bees including bumble bees; host for swallowtail and other butterflies fruit for birds; nesting cover; .

Small flowers for small pollinators, host for swallowtails, early forage, insects/ fruit for birds such as nuthatches, grosbeaks, orioles, vireos, jays and small mammals

#1 Forage for pollinators including honey bees; host for butterfly and moth #2 caterpillars Forage for pollinators; special value to #2 native bees; birds eat seeds

Yellowish- Remove dead green; Mar- wood if necessary Apr Intolerant of flooding; trim hard in spring if it Yellowish- outgrows space green; MarApr Y Low maintenance; remove stems as needed Insignifica nt; Y Prefers consistent moisture - mulch root zone; Yellow; remove suckers Mar-Jul Y as preferred. Low maintenance; prune dead or Pink; Apr- broken branches May Y as needed Do not deadhead; remove dead canes as needed; do not crowd Pink; JunJul Choose disease resistant varieties when possible; manage Japanese Color beetles; remove varies; dead wood in May-Sep spring Watch for fungal diseases

Low

Sandy or clay soils

3-6'

#2 Forage for bees, butterfliesand flies

12-18"

Forage for many pollinators

Prune as needed immediately after bloom. Shrubs may be cut down to the ground in early spring for rejuvenation. May be susceptible to White or fireblight or pink; May- powdery mildew Jun Y Prune as needed in late winter; Can be cut down to ground in early spring for rejuventation. May be Yellow; Jun susceptible to Nov spider mites Remove suckers to prevent unwanted spread

Clay, loam, sand

White; June

Prune back every 5 years to rejuvenate thick growth habit Low maintenance, very drought tolerant; prune after flowering Prune as needed immediately after bloom. Shrubs may be cut down to the ground in early spring for rejuvenation.

Once mature, prune a couple of the largest branches to 6" off the ground; every few years, trim all height back to shorter than 18" White; Apr- for rejuvenation Jun Light yellow; AprJun Yellow; May-Jun

Dry, rocky or sandy soils

White; May-Jun

Y Prune 1/3 of plant in late winter

Early forage for bees and flies; fruits for birds

Early forage for early bees; shelter for overwintering insects;Shelter for birds and other small animals; small flowers for native pollinators; berries important winter food for many birds #2 and animals; ; deer/rabbit resistant Forage for bees - special value to native bees and honey bees; nesting materials for native bees; larval host; supports biocontrol insects; fruits are eaten by birds and small mammals; #5 deer may browse; rabbit resistant Provides nectar for bees, hummingbirds and butterflies. Host for hoary comma butterfly. Birds, bears and rodents eat fruit; rabbit resistant #1 Early bees and migrating hummingbirds visit flowers, Birds such as grosbeaks, robins, jays, towhees, and wildlife eat fruits

Foraging for many pollinators; hips for birds and other wildlife; ; deer/rabbit resistant

Simple flowers can attract bees and flies; the more petals make it difficult for pollinators to visit; birds and mammals will eat hips #1 Shelter for birds and other small animals; pollen and nectar for pollinators; berries for birds such as grouse, bluebirds, juncos, grosbeaks, and other wildlife; ; deer/rabbit #1 resistant Forage for pollinators, special value to native, bumble, and honey bees; nesting for native bees; birds and #2 other wildlife eat fruits Pollinated by a variety of bees and butterflies, birds such as finches and chickadees and other wildlife eat fruits

Host for mourning cloak butterflies and Weidemeyer's admirals; shelter

Attachment C - Draft Boulder Approved Tree and Plant List Sambucus racemosa

Red-berried elder

Shepherdia argentea

Silver buffaloberry

Symphoricarpos albus

Common snowberry

Symphoricarpos occidentalis

Symphoricarpos orbiculatus

Syringa spp.

Teucrium chamaedrys

High

Snowberry

Lilac

Don't overwater

Clay, loam, sandy, gravelly

12'

Moderate

Full sun shade

Medium drainage

3-6'

Moderate

Adaptable - dry, Full sungravelly to wellpart shade drained loams

3-6'

White/gree n; May-Jun

Full sun

Low - modeFull sun

Adaptable - welldrained sand, loam, clay

Well-drained, rich

Not too rich, welldrained

6-8'

Moderate

Full sun

Well-drained, tolerant 6-10' of clay

Yucca baccata

Banana yucca

Very low low

Full sun

Well-drained soils, dry

Yucca filamentosa

Adam's needle

Very low low

Full sun

Yucca

Low

Full sun

Well-drained soils, dry Well-drained soils, dry

Full sun

Deep, sandy or rocky 3' soils

Yucca glauca

White; May-Jun

Full sunpart sun

Weigela

Weigela florida

8-15'

Very low low

Moderate

8-12'

Prune rhizomes in winter, make sure plant has White; Apr- good air May circulation Can spread by suckers in irrigated areas Pink; JunJul Y Remove root White/ suckers and pink; Jun- runners to Sep manage spread Y

Moderate- Full sun low shade

Red coralberry

Germander

Full sunMoist, rich, slightly part shade acidic loamy soils

6-8'

9-12'

Needs good air circulation; remove faded flowers before seed set to have bigger bloom Shades of following year; purple and prune white; Apr- immediately after May flowering Pinch leggy stems to promote bushier habit; may die back in Purplish- harsh winters pink; Jul Blooms on old and new wood prune to shape Pink; May- immediately after Jun flowering

Forage for beneficial insects and hummingbirds; nesting structure for #5 native bees; Forage for pollinators, special value to native bees; Habitat and food for birds such as robins, sparrows, red-winged blackbirds ;deer/rabbit resistant #5 Shelter for birds and other animals; small flowers attract small pollinators and hummingbirds; berries for wildlife; sphinx moth larval host; deer/rabbit #1 resistant Shelter for birds and other animals; small flowers attract small pollinators; berries for wildlife; deer/rabbit #1 resistant Shelter for birds and other animals; small flowers attract small pollinators and other beneficial insects; berries for wildlife; deer/rabbit resistant #1 Forage for many generalist pollinators; deer/rabbit resistant

#2 Forage for generalist bees and butterflies; deer/rabbit resistant

#1 Forage for bees, butterflies, hummingbirds

3’

2-3'

2-4'

2-3'

White; May-Jun White; JunAug

White; Jun

Tan; JunSep

Tan; AugNov

Specialist moth relationship; shelter for small animals; deer/rabbit resistant Specialist moth relationship; shelter for small animals; deer/rabbit resistant Host for yucca moth, protection for wildlife; deer/rabbit resistant

#1 #1

Grasses and grass-like plants

Achnatherum hymenoides

Indian ricegrass

Low

Andropogon gerardii

Big bluestem

High - low Full sun

Bouteloua curtipendula

Sideoats grama

Moderatelow Full sun

Moist, sand, loam, clay Dry to medium moisture soils, well drained

Bouteloua dactyloides

Buffalograss

Moderatelow Full sun

Dry well drained soil, does not like sand

Bouteloua gracilis Calamovilfa longifolia Carex spp. Deschampsia caespitosa

Blue grama

Prairie sandreed Sedge

Tufted hairgrass

0.5'

1.5-2' 10' 1'

Y Y Y

Blue oat grass

Well drained soil

2.5'

Needle-and-thread

Moderate- Full sun

Well drained soil

1.5'

N/A

New Mexico feathergrass

Moderatelow Full sun

Alkaline to neutral

2-3'

Poor, disturbed

2.5'

N/A Light purple; May-Jul

1.5'

Elymus trachycaulus

Slender wheatgrass

High

Sandy, gravelly soil, Full sun rocky slopes Full sun part shade Sandy or rocky soil

Low

Sun - part shade

Arizona fescue

Festuca glauca

Blue fescue

Festuca idahoensis

Idaho fescue

Festuca ovina

Gravelly, rocky soil

Hordeum jubatum

Foxtail barley

High-low

Full sun

Koeleria macrantha

Junegrass

Highmoderate

Full sun - Sandy, rocky soils, part shade dry

Muhlenbergia asperifolia

Alkali muhly

Muhlenbergia montana Muhlenbergia reverchonii 'PUND01S'

Mountain muhly UNDAUNTED ruby muhly

Tan; JulOct Yellow; JulAug Green; May

Well-drained, rocky, 1' poor soil Adaptable from fertile 3' to rocky soils Well-drained loam, 1' sand

High-low

Hesperostipa neomexicana

0.5'

Moderatelow Full sun Moderate Full sun Moderate- Full sunlow part sun Moderatelow Full sun

Canada wildrye

Thickspike wheatgrass

Hesperostipa comata

1.5-2'

Tan; JunNov Tan; AprDec (blooms opportunis tically

Yellow; Jun Yellow, green, brown; Mar-Jun Yellow, green; May Aug Green; JunJul Green, brown; JulSep Light green, insignifica nt; Jun-Jul Yellow; Apr Jul Green; JunJul Bluishbrown; Jun

Elymus lanceolatus

Helictotrichon sempervirens

1.5-2.5'

ModerateDry to medium well low Full sun 0.75-2' drained soils Full sunModerate part sun Well-drained 6' Moderate"Loose" loamy well1' low Full sun-pa drained Full sunLow 3' part shade Wet, alkaline Well-drained, porous, acid or calcareous Moderate- Full sunsand, loam, clay or low 2-6' part shade limestone

Elymus canadensis

Festuca arizonica

2-6'

1-5'

Moist, alkaline, loamy Part shade or clay 2'

1.5' 3' 1'

Low ModerateFull sun low

Rocky

2-3'

Low

Clay, loam

1-2'

Full sun

Green; April-June Green, purple, brown; JunOct Yellow; Jun Jul Reddish; Aug-Oct

Host for skippers and satyrs, pollen for bees, seeds for birds, shelter; forage seed for grazing animals Shelter, nesting for native bees, host for skippers, seeds for birds; #1 deer/rabbit resistant Host plant for satyr butterflies; shelter for small animals. Nesting material for seed birds Host plant for satyr butterflies, host for green skipper; shelter for small animals

seed Host plant for satyr butterflies; shelter for small animals. Nesting material for birds; seeds/ insects for sparrows, chickadees, nuthatches, finches Forage and shelter for mammals and birds Deer/rabbit resistant

seed seed

F15 Forage and shelter for mammals and F15 birds; host for umber skipper Nesting and shelter, seeds for birds and small mammals, host for Zabulon skipper; deer/rabbit resistant seed Shelter; seeds for birds and small mammals seed

seed Shelter F15

F15 Shelter, host for skippers F15 Shelter F15 Shelter; deer/rabbit resistant F15 Host plant for satyr butterflies; shelter seed for small animals Shelter; deer/rabbit resistant seed Shelter; deer/rabbit resistant seed

Host plant for satyr and skipper butterflies; shelter for small animals; seeds for birds Shelter; host for cutworm moths

Y Y

seed

seed Shelter seed Shelter; deer/rabbit resistant F15

Attachment C - Draft Boulder Approved Tree and Plant List Nassella viridula

Green needlegrass

Panicum virgatum

Switchgrass

Pascopyrum smithii Pennisetum alopecuroides 'Little Bunny'

Full sunpart sun

Disturbed, finetextured, dry

High - low Full sun Full sunModerate part sun ModerateFull sun low

Dry to moist soils

Moderate

Western wheatgrass Little Bunny fountain grass

Most soils Loam, Sand; adaptable to pH Loam, Sand; Part shade adaptable to pH Loamy, well-drained soil with high organic Part shade matter

3-5'

2-4'

Adaptable

Pennisetum setaceum

Fountain grass

Moderate

Poa palustris

Fowl bluegrass

Poa secunda

Sandberg's bluegrass

Low ModerateFull sun low

Schizachyrium scoparium

Little bluestem

Highmoderate

Schoenoplectus pungens

Common three-square

Moderate

Sorghastrum nutans

Indian grass

Spartina pectinata

Prairie cordgrass

Yellow; Apr May Green; Aug Nov Yellow; May-Jun Buff; JulSep Rose; JunSep

Full sun Full sun

Alkaline, salty

Buff; Jun Dec Tan; JunJul

High

Full sun

Moist rich soils

Tan; AugOct

High-low

Full sun

Moist, rich

5-8'

Yellow; Jun

Sporobolus airoides

Alkali sacaton

Low

Full sun

Sporobolus cryptandrus

Sand dropseed

Low

Full sun

Sporobolus heterolepis

Prairie dropseed

Moderate- Full sunlow part sun

Sporobolus wrightii

Giant sacaton

Full sunpart sun

Alkaline, fine-textured sand, loam or clay, 4' saline tolerant Sand or sandy loam, 3' disturbed

Dry, sandy

5-7'

4-5'

ModerateClay, loam, sandy low

Y Y

Yellow; Apr Yellow; Apr May

Well drained soil, sandy, clay, loam

Shelter for ground-nesting birds, seed especially waterfowl Host plant for satyr butterflies; shelter F15 for small animals Birds eat seeds seed Birds eat seeds F15 Shelter F15

seed Shelter

seed Host plant for skippers and satyr butterflies; nesting for native bees shelter for small animals; seeds for birds Forage for wetland birds; host for skippers; shelter Host plant for skippers and satyr butterflies; shelter for small animals; seeds for birds Shelter

Y Y Aug-Oct

seed seed

Shelter, seeds for birds and small mammals

Yellow; Jun Nov Yellow; May-Nov Pink, yellow, green, brown; JunAug Blondebronze; Aug-Oct

seed Nesting for native bees, shelter, seeds seed for birds and small mammals Nesting for native bees, shelter, seeds for birds and small mammals

seed Shelter; seeds for birds and small mammals;

seed

Trees

Species Name

Common Name

Acceptable Cultivars

Approved for Regulated WUI Areas IR1, IR2 and Water Use IR3 in HIZ 5'-30' (hydrozon e) (Yes/No)

Mature Size (Height x Spread in Mature Size Category ft)

Mature Canopy Area (sq. ft)

Pest/Abiotic Issues

Flowers

Biodiversity and Wildlife

Approved for Approved for Minimum Size Private Property Public Street ROW (Yes/No) Category (Yes/No)

Colorado Native

Approved for Parks Properties (Yes/No)

Approved for Approved for Approved for Approved for Approved for Approved for Approved for Approved for Approved for use in use in Central Boulder use in Colorado Approved for use in Central use in use in East use in use in North use in South Southeast use in Palo Park University Hill University Boulder Crossroads Boulder Gunbarrel Boulder Boulder Boulder Subcommunity Subcommunity Subcommunity Subcommunity Subcommunity Subcommunity Subcommunity Subcommunity Subcommunity Subcommunity (Yes / No) (Yes / No) (Yes / No) (Yes / No) (Yes / No) (Yes / No) (Yes / No) (Yes / No) (Yes / No) (Yes / No)

DECIDUOUS TREE SPECIES

Acer campestre

Hedge maple

Acer ginnala

Ginnala maple

Acer glabrum

Rocky Mountain maple

Acer grandidentatum

Bigtooth maple

Acer griseum

Paperbark maple

Queen Elizabeth

Yes

Low to Moderate

Medium

30 x 30

707

Yes

Moderate

Small

15 x 15

177

Yes

Rocky Mountain Glow

Low to Moderate

Small

Aesculus glabra

Ohio buckeye

Yes

2-inch caliper

Yes

1.5-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

314

Insignifica nt Insignifica nt

Medium

30 x 30

707

Insignifica nt

Large

40 x 40

1256

Insignifica nt

Yes

707

Insignifica nt

Low to Moderate

Yellow buckeye

Yes

491

Yes

Aesculus flava

Yes

25 x 25

For ROW, 'Sensation' is only acceptable boxelder

Yes

Hot Wings, Pattern Perfect

Yes

25 x 20

Boxelder

Tatarian maple

Small

Acer negundo

Acer tataricum

Medium

Yes

Fall Fiesta, Legacy, Caddo

Yes

Low

State Street

Sugar maple

1.5-inch caliper

Moderate

Miyabe maple

Acer saccharum

Insignifica nt

Yes

Acer miyabe

Sycamore maple

177

Yes

Low to Moderate

Acer pseudoplatanus

20 x 15

Insignifica nt Insignifica nt

Nectar for pollinators/ invertebrates (hoverfly,bees (honey bees, cellophane bees); hoverflies and ladybugs also go after aphids, small mammals, birds; shelter and nesting 2-inch caliper

Yes

Moderate

Low to Moderate

Moderate

Large

Small

Large

Medium

35 x 30

60 x 45

20 x 15

60 x 40

25 x 25

1590

177

1256

491

Some cultivars may develop Insignifica chlorosis in alkaline soils nt Clusters of yellowwhite flowers in the early spring Showy 6- Prone to leaf scorch in hot inch panicles and dry sites of creamy yellow flowers in the spring Showy creamy white to greenishyellow flowers in the spring

Yes No

Insect pollinators, host for geometrid moths and winter moths, browse for large mammals, wetland indicator, seeds for small mammals, birds; shelter and nesting 1.5-inch caliper Host for leaf blotch miner moths, browse for large mammals, wetland indicator, seeds for small mammals, birds; shelter and nesting 2-inch caliper Nectar for bees and other pollnators; shelter and nesting 1.5-inch caliper Nectar for bees and other pollinators; urban birds; shelter and nesting 2-inch caliper Special value to honey bees, host for cecropia silkmoth and geometrid moths; seeds and shelter for birds and other wildlife; shelter and nesting 2-inch caliper Nectar for bees and other pollinators; host for leaf miner moths, geometrid moths; shelter and nesting 2-inch caliper Special value to honey bees; shelter and nesting

No Nectar for bees and other pollinators

No Nectar for bees, butterflies, hummingbirds and other pollinators, host for leaf miner and tiger moths, seeds for small mammals; shelter and nesting No Nectar for hummingbirds, bees (esp. honey bees); host for dagger moths and geometrids; shelter and nesting

Attachment C - Draft Boulder Approved Tree and Plant List

Aesculus glabra var. arguta

Aesculus hippocastanum

Texas buckeye

Common horsechestnut

Aesculus x carnea

Red horsechestnut

Alnus glutinosa

European alder

Alnus incana ssp. tenuifolia

Thinleaf alder / Mountain alder

Amelanchier alnifolia

Western serviceberry

Amelanchier arborea

Downy serviceberry

Amelanchier canadensis

Shadblow serviceberry

Amelanchier laevis

Allegheny serviceberry

Amelanchier utahensis

Utah serviceberry

Betula occidentalis

Water birch / Rocky Mountain birch

Betula papyrifera

Paper birch

Carpinus betulus

European hornbeam

Carpinus caroliniana

Yes

Briotti, Fort McNair

Snowcloud, Spring Flurry

Fastigiata, Frans Fontaine

American hornbeam

Moderate

Medium

Large

30 x 30

60 x 50

707

1964

Yes

Moderate

Medium

35 x 30

707

Yes

Moderate to High

Medium

30 x 15

177

Yes

Saskatoon

Low to Moderate

High

Small

40 x 40

1256

Yes

Moderate

Small

10 x 8

Yes

Low to Moderate

Small

20 x 15

177

Yes

Moderate to High

Small

20 x 15

177

Yes

Moderate

Small

15 x 15

177

Yes

Low to Moderate

Small

8x8

Yes

Moderate

Small

15 x 15

177

Yes

Moderate

Medium

30 x 15

177

Yes

Moderate

Medium

40 x 30

707

Yes

Moderate

Medium

30 x 30

Clusters of fragrant yellow to creamcolored flowers in the spring Prone to leaf Spring flowering scorch in hot and dry sites whitepinkish flowers Prone to leaf Showy 8- scorch in hot and dry sites inch panicles of pink or red coneshaped flowers in the spring Small purplishbrown catkins in early spring Small purplishbrown catkins in early spring Clusters of showy, white flowers White, 5petaled flowers Showy, slightly fragrant, white flowers in drooping clusters Susceptible to Small, fireblight slightly fragrant flowers Clusters of white, rose-like flowers Yellow to brown catkins Yellow to brown catkins Insignifica nt

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper Nectar and pollen for bees (esp honey bees), host for Hackberry Emperor, American Snout, birds (inc. robins and songbirds) eat fruit; shelter and nesting 2-inch caliper Host for wild cherry sphinx, tawny emperor, American snout, question mark, mourning cloak butterflies; birds and mammals eat fruit; shelter and nesting 2-inch caliper Host for American snout, hackberry emperor, mourning cloak, birds and mammals eat fruit; wetland indicator; shelter and nesting 2-inch caliper Nectar and pollen for bees, special value to native bees esp bumble bees, nesting for native bees, nectar for butterflies and hummingbirds; seeds and flowerbuds eaten by birds 1.5-inch caliper

Yes

Nectar for hummingbirds, bees (esp. honey bees); host for dagger moths and geometrids; shelter and nesting No Nectar for hummingbirds, bees (esp. honey bees); shelter and nesting

No Important larval food source for many native invertebrates

Yes Important larval food source for many native invertebrates Yes

Yes Shelter and nesting No

707

Insignifica nt

Yes

Low to Moderate

Large

50 x 30

707

Showy clusters of large white orchidlike flowers in late spring / early summer

Yes

Low to Moderate

Medium

45 x 40

1256

Insignifica nt

Yes

Common hackberry

Yes

Low to Moderate

Large

50 x 50

1964

Insignifica nt

Yes

Celtis reticulata

Netleaf hackberry

Yes

Low

Medium

30 x 30

707

Cercis canadensis

Eastern redbud

Yes

Moderate

Small

25 x 25

491

Catalpa speciosa

Western / Northern catalpa

Celtis laevigata

Sugar hackberry

Celtis occidentalis

All Seasons, Magnifica

Insignifica nt Striking pink to purple flowers in early spring

Yes

Host for striped hairstreak; mammals and birds (including warblers, grouse and pheasant) eat seeds; shelter and nesting; host for eastern tiger swallowtail Host for catalpa sphinx moth, as well as tiger and geometrid moths; special value to honey bees; wetland indicator; shelter and nesting

Attachment C - Draft Boulder Approved Tree and Plant List

Cladrastis kentukea

Yellowwood

Yes

Moderate

Medium

40 x 40

1256

Cornus mas

Cornelian cherry dogwood

Yes

10 x 15

177

Turkish filbert

Yes

Moderate Low to Moderate

Small

Corylus colurna

Medium

45 x 30

707

Crataegus ambigua

Russian hawthorn

Yes

Very Low to Low

Small

20 x 15

177

Crataegus chrysocarpa

Fireberry hawthorn

Yes

Moderate

Small

20 x 15

177

Crataegus crus-galli

Cockspur hawthorn

Yes

Moderate

Small

10 x 15

177

Crataegus erythropoda

Crataegus laevigata

Thornless

Cerro hawthorn

English hawthorn

Crimson Cloud, Paul's Scarlet

Yes

Low to Moderate

Small

8 x 10

Yes

Low to Moderate

Small

15 x 15

177

Crataegus lavellei

Lavalle hawthorn

Yes

Moderate

Small

20 x 15

177

Crataegus mollis

Downy hawthorn

Yes

Low to Moderate

Small

20 x 15

177

Crataegus rivularis

River hawthorn

Yes

Moderate

Small

10 x 10

Yes

Low to Moderate

Small

20 x 20

314

Crataegus saligna

Crataegus succulenta

Crataegus viridis

Willow hawthorn

Fleshy hawthorn

Green hawthorn

Yes

Winter King

Low to Moderate

Small

Yes

Low to Moderate

Small

10 x 10

15 x 15

177

Crataegus x mordenensis

Toba hawthorn

Toba

Yes

Low to Moderate

Small

15 x 15

177

Fagus sylvatica

European beech

Purpurea, Tricolor

Yes

Moderate

Large

50 x 40

1256

Gleditsia triacanthos inermis

Thornless honeylocust

For ROW, 'Shademaster' is the only approved cultivar

Yes

60 x 50

1964

Kentucky coffeetree

Espresso, Stately Manor, Decaf

Yes

Low Low to Moderate

Large

Gymnocladus dioicus

Large

60 x 50

1964

Koelreuteria paniculata

Goldenrain tree

Yes

Low

Medium

35 x 35

962

Liriodendron tulipifera

Maackia amurensis

Magnolia acuminata

Magnolia Galaxy

Tuliptree

Amur maackia

Cucumbertree magnolia

Galaxy magnolia

Yes

Moderate

Large

Small

Large

Small

60 x 35

25 x 25

55 x 30

25 x 15

962

491

707

177

Fragrant, white, Wisterialike racemes in early summer Clusters of bright yellow flowers in early spring Insignifica nt Clusters Good resistance of bright to fireblight white flowers in early spring Clusters of white flowers in spring Clusters of white flowers in spring Clusters of white flowers in spring Clusters All cultivars are of white susceptible to flowers in fireblight spring Clusters All cultivars are of white susceptible to flowers in fireblight spring Clusters Good resistance of white to fireblight flowers in spring Clusters of white flowers in spring Clusters of white flowers in spring Clusters of white flowers in spring Clusters Fewer disease of white issues than flowers in other hawthorns spring Clusters of white flowers in spring Insignifica nt 'Sunburst' can have significant Insignifica fungal canker issues nt Insignifica nt Showy panicles of golden yellow flowers in midsummer Showy yellowgreen large tulipshaped flowers in early summer Clusters of fragrant, white, pea like flowers Slightly fragrant, greenishyellow tulip-like flowers Profusion of large, deep reddishpurple flowers

Nectar and pollen for bumble bees and other long-tongued bees; shelter and nesting

2-inch caliper

Yes

1.5-inch caliper 2-inch caliper

Yes

No No

Mammals eat seeds; shelter and nesting Spring forage for bees (esp honey bees) and pollinating flies; fruit for birds, such as robins; shelter and nesting

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

1.5-inch caliper

Yes

2-inch caliper

Yes

1.5-inch caliper

Yes

2-inch caliper

Yes

1.5-inch caliper

Yes

Important larval and adult food source for many native invertebrates Yes

Spring forage for bees (esp honey bees) and pollinating flies; fruit for birds, such as robins; shelter and nesting Spring forage for bees (esp honey bees) and pollinating flies; fruit for birds, such as robins; shelter and nesting

Yes

Yes Important larval and adult food source for many native invertebrates Yes

Spring forage for bees (esp honey bees) and pollinating flies; fruit for birds, such as robins; shelter and nesting

No No

Nuts for mammals and birds; shelter and nesting Nectar for bees and butterflies; browse for large mammals, host for silver spotted skipper; shelter and nesting Pollen for bumble bees and longhorned bees; shelter and nesting Pollen and nectar for bees, esp. honeybees; shelter and nesting

No Abundant nectar and pollen for flies, beetles, honey bees, bumble bees, other long-tongued bees, hummingbirds; host for geometrid and saturniid moths; shelter and nesting No Nectar and pollen for bees; shelter and nesting

No Pollinated by beetles and flies, possible host for black swallowtails; seeds for towhees and other groundfeeding birds; shelter and nesting No Pollinated by beetles and flies, possible host for black swallowtails; seeds for towhees and other groundfeeding birds; shelter and nesting No

Attachment C - Draft Boulder Approved Tree and Plant List

Magnolia x soulangiana

Malus sylvestris

Saucer magnolia

Crabapple

Ostrya virginiana

American hophornbeam

Phellodendron amurense

Amur corktree

Populus x acuminata

Populus angustifolia

Populus deltoides

Yes

Only cultivars resistant to fireblight allowed in the ROW; Indian Magic, Prairiefire, Royal Raindrops, Spring Snow, Thunderchild

His Majesty, Macho, Eyestopper

Lanceleaf cottonwood

Prunus cerasus

Medium

30 x 25

491

Yes

Moderate

Large

40 x 45

1590

Moderate

Montmorency

Important to select a cultivar with good to excellent resistance to the following: fireblight, scab, Varies by cedar apple rust, and cultivar typically mildew; only fragrant resistance clusters cultivars of white to allowed on public property varies by pink cultivar flowers

Yes

Small

Large

varies by cultivar

491

Low to Moderate

Eastern cottonwood

Sour cherry

25 x 25

Low to Moderate

Yes

Populus deltoides ssp. monilifera Plains cottonwood

Small

Yes

Narrowleaf cottonwood

Moderate

50 x 30

40 x 30

70-60

707

2827

Hanging catkins in the spring before the leaves

707

Yes

Moderate

Large

70 x 60

2827

Yes

Moderate

Small

15 x 15

177

Amur chockecherry

Yes

Moderate

Small

20 x 20

314

Prunus mandshurica

Manchurian apricot

Yes

Moderate

Small

15 x 15

177

Prunus padus

Mayday tree

Yes

Moderate

Small

20 x 20

314

Prunus pennsylvanica

Pin cherry

Yes

Moderate

Small

25 x 15

177

Prunus serotina

Black cherry

Yes

Moderate

Large

40 x 30

707

Ptelea trifoliata

Chokecherry

Common hoptree

Sucker Punch, Canada Red

Yes

Low to Moderate

Very Low to Low

Small

25 x 15

20 x 20

Insignifica nt Insignifica nt Susceptible to Hanging several foliar catkins in fungal diseases the spring before the leaves Susceptible to Hanging several foliar catkins in fungal diseases the spring before the leaves

Prunus maackii

Prunus virginiana

Large saucershaped flowers in shades of purple, pink and white in the spring

177

314

Hanging catkins in the spring before the leaves Individual white or pink flowers Dense racemes of fragrant creamywhite flowers Spring display of pink flowers Dense racemes of fragrant creamywhite flowers Clusters of white flowers Dense racemes of fragrant creamywhite flowers Dense racemes of fragrant creamywhite flowers Sprays of tiny starshaped greenishwhite flowers

Seeds for towhees and other groundfeeding birds; shelter and nesting

1.5-inch caliper

Yes

1.5-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

2-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

Pollen and nectar for bees, esp. honey bees; host for geometrid and leaf miner moths; some have seeds for birds and mammals; shelter and nesting

Seeds for songbirds and small mammals; wetland indicator; shelter and nesting Shelter and nesting

No Important larval food source for many native invertebrates

Yes Important larval food source for many native invertebrates

Yes

2-inch caliper Important larval food source for many native invertebrates

Yes

No Nectar and pollen for bees (esp. honey bees) and fruit for songbirds and small mammals; shelter and nesting

No Special value to native bees; host for western tiger swallowtails; fruit for songbirds and mammals; shelter and nesting

Yes Pollinated by carrion flies; host for two-tailed and western tiger swallowtails, shelter and nesting

Yes

Attachment C - Draft Boulder Approved Tree and Plant List

Yes

Low to Moderate

Medium

30 x 20

314

Abundant Moderately resistant to , fivepetaled fireblight flowers in early spring known for their unpleasa nt odor

White oak

Yes

Low to Moderate

Large

65 x 65

3318

Insignifica nt

Quercus bicolor

Swamp white oak

Yes

Moderate

Large

55 x 55

2376

Insignifica nt

Quercus gambelii

Gambel oak

Yes

Very Low to Low

Small

20 x 20

314

Insignifica nt

Yes

Quercus imbricaria

Shingle oak

Yes

Moderate

Large

50 x 50

1964

Insignifica nt

Pyrus calleryana

Flowering pear

Quercus alba

Cleveland Select, Chanticleer, Autumn Blaze

Nectar and pollen for insects (bees, flies); fruit for songbirds and small mammals; shelter and nesting

Susceptible to oak rough bullet gall wasp choose gall-less tree stock for parks & ROW as galls may attract yellow Insignifica jackets

Yes

Low to Moderate

Large

70 x 70

3848

Chinkapin oak

Yes

Low to Moderate

Large

40 x 50

1964

Insignifica nt

Quercus undulata

Wavy-leaf oak

Yes

Very Low to Low

Small

10 x 10

Salix amygdaloides

Peachleaf willow

Yes

Moderate

Large

35 x 30

707

Salix bebbiana

Bebb willow

Yes

Moderate

Small

10 x 10

Salix nigra

Black willow

Yes

Moderate

Large

40 x 40

1256

Salix scouleriana

Scouler's willow

Yes

Moderate

Medium

30 x 30

707

Sorbus aria

Whitebeam tree

Yes

Moderate

Medium

40 x 25

491

Sorbus aucuparia

Mountain-ash

Yes

Moderate

Medium

30 x 15

177

Sorbus hybrida

Oakleaf mountain-ash

Yes

Moderate

Small

25 x 15

177

Sorbus scopulina

Greene's mountain-ash

Yes

Low to Moderate

Small

10 x 10

Styphnolobium japonicum

Japanese pagoda tree

Yes

Moderate

Large

50 x 50

1964

Quercus macrocarpa

Bur oak

Quercus muehlenbergii

Syringa pekinensis

Syringa reticulata

Tilia americana

Chinese tree lilac

Japanese tree lilac

American linden

Bulletproof

Cardinal Royal

China Snow

Ivory Silk

Boulevard, Legend, Frontyard, American Sentry, Redmond

Yes

Moderate

Small

Large

20 x 15

25 x 15

60 x 40

177

1256

Insignifica nt Yellowgreen catkins Yellowgreen catkins Yellowgreen catkins Yellowgreen catkins Clusters Susceptible to of white fireblight flowers Clusters of white flowers Clusters Susceptible to of white fireblight flowers Clusters of white flowers Fragrant greenwhite to yellow flowers in midsummer Resistant to Large clusters powdery mildew of creamywhite, fragrant flowers Large clusters of creamywhite, fragrant flowers May see minor defoliation from Japanese beetle

Fragrant yellow flowers in the spring

Yes

2-inch caliper Honey bees may visit oak gall honeydew; host for geometrid, tiger, leaf miner and other moths; acorns for birds and small mammals; shelter and nesting 2-inch caliper Honey bees may visit oak gall honeydew; host for geometrid, tiger, leaf miner and other moths; acorns for birds and small mammals; shelter and nesting 2-inch caliper Host for purple hairstreak (CO state butterfly) geometrid, tiger, leaf miner and other moths; acorns for birds and small mammals; shelter and nesting 1.5-inch caliper Honey bees may visit oak gall honeydew; host for geometrid, tiger, leaf miner and other moths; acorns for birds and small mammals; wetland indicator; shelter and nesting 2-inch caliper Honey bees may visit oak gall honeydew; host for geometrid, tiger, leaf miner and other moths; acorns for birds and small mammals; shelter and nesting

Yes

2-inch caliper

Yes

1.5-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

2-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

2-inch caliper

Yes

Important adult and larval food source for many native invertebrates Host for pyralid moths; nectar and pollen for bees and other insects; shelter and nesting

No Spring forage for bees, butterflies, hummingbirds; shelter and nesting

Spring forage for bees, butterflies, hummingbirds; host for blinded sphinx moths, mourning cloak and question mark butterflies; associated with firefly habitat (attracts prey); shelter and nesting mature trees may have cavities for wood ducks, woodpeckers, and other species

Attachment C - Draft Boulder Approved Tree and Plant List May see defoliation from Japanese beetle

Tilia cordata

Littleleaf linden

Yes

Moderate

Medium

35 x 35

962

Tilia tomentosa

Silver linden

Yes

Moderate

Large

50 x 30

707

Tilia x flavescens

Glenleven linden

Yes

Moderate

Large

40 x 40

1256

Ulmus americana

Ulmus davidiana

Ulmus davidiana var japonica 'Morton'

American elm

David elm

*check with Boulder Forestry for approved varieties and cultivars

Choice City

Accolade elm

Yes

Xanthoceras sorbifolium

Golden yellowhorn

Clear Creek

Varies CONIFEROUS TREE SPECIES

Fruit trees

Yes

Abies concolor

white fir

Cedrus atlantica

atlas blue cedar

Yes

Low to Moderate

Moderate

Low to Moderate

Very Low to Low Moderate to High

European larch

Metasequoia glyptostroboides

dawn redwood

Picea glauca

white spruce

Picea pungens

No No No No

Moderate

pinyon pine

limber pine

giant sequoia

50 x 25

625

Small Large Large Large

No No

850

50 x 15

375

263

40 x 35

750

No Varies

Nectar and pollen for insects, esp. bees

Yes Increased susceptibility to Ips beetle post construction or if irrigation insufficient

Shelter and nesting Forage for many mammals; shelter and nesting Host for geometrid, tiger moths; forage for many mammals; shelter and nesting

Increased susceptibility to pitch mass borer in irrigated sites

Host for geometrid, tiger, satyr, and tortricid moths; seeds feed many mammals and birds including turkeys, jays, rodents, deer, bears; shelter and nesting Host for geometrid, tortricid moths and western pine elfin; seeds feed many mammals and birds; shelter and nesting Host for pine white and pandora pinemoth, as well as geometrid, owlet, and tortricid moths; seeds feed many birds (turkeys, nuthatches, grosbeaks, crossbills) and mammals (chipmunks, squirrels); large mammals (deer, porcupines, elk) graze on needles;nesting and shelter

2000

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper Fruit trees for food production are prohibited on properties west of Broadway Avenue to protect wildlife by reducing the incidence of encounters with bears in urban areas.

Yes

5-foot height 5-foot height

Yes Yes

No No

Yes Yes

5-foot height

Yes

5-foot height

Yes

5-foot height

Yes

5-foot height

Yes

5-foot height

Yes

5-foot height

Yes

5-foot height

Yes

5-foot height 5-foot height

Yes No

No No

Yes Yes

Host for tortricid moth; seeds feed many birds (turkeys, nuthatches, grosbeaks, crossbills) and mammals (chipmunks, squirrels); large mammals (deer, porcupines, elk) graze on needles and bark;nesting and shelter Yes

40 x 30

Yes

1350

688

Yes

Host for geometrid, tortricid and owlet moths; seeds for songbirds and small mammals; deer, porcupines feed on foliage and bark; shelter and nesting 5-foot height Shelter and nesting 5-foot height

Yes

50 x 20

Nectar and pollen for insects, esp. bees

1125

Large

Shelter and nesting

Yes

50 x 30

Yes

Shelter and nesting

Yes

70 x 35

Large Large

Yes

25 x 20

2-inch caliper

Host for mourning cloak, question mark, painted lady; seeds for birds; shelter and nesting

Large

Moderate

Yes

30 x 15

Low to Moderate

60 x 25 85 x 20

50 x 30

Low

Yes

Large

Sequoiadendron giganteum

688

Low

southwestern white pine

Rocky Mountain Douglas-fir

50 x 25

Low

Ponderosa pine

Pseudotsuga menziesii var. glauca

Varies

Medium

Pinus strobiformis

177

Varies

Medium

Pinus ponderosa

20 x 15

Very Low

Vanderwolf' not allowed (does not perform well in Colorado)

962

Large

No Pinus flexilis

55 x 35

1590

Small

Low to Moderate

bristlecone pine

45 x 45

1964

Full sun

Low to Moderate

blue spruce

Pinus edulis

Large

70 x 50

Large Low to Moderate Moderate to High Moderate

Pinus aristata

Medium

Moderate No

Larix decidua

Large

Fragrant yellow flowers in the spring Fragrant yellow flowers in the spring Fragrant May see minor defoliation from yellow flowers in Japanese beetle the spring Choose a variety/cultivar resistant to Insignifica Dutch elm disease nt Resistant to elm leaf beetles & Dutch elm Insignifica disease nt Resistant to elm leaf beetles, European elm scale & Dutch Insignifica elm disease nt Very showy white flowers in May Varies Varies

Yes

Host for pine white and geometrid moths; seeds feed many birds (chickadees, finches, grosbeaks, crossbills) and mammals (chipmunks, squirrels); large mammals (deer, porcupines, elk, beaver, rabbits) graze on needles;nesting and shelter Nesting and shelter

Attachment C - Draft Boulder Approved Tree and Plant List Taxodium distichum

baldcypress

Use only straight genus/species - no cultivars allowed in city parks & ROW

Moderate to High

50 x 25 Large

Seeds for birds and small mammals; shelter and nesting

1050 Yes

5-foot height

Yes

Attachment C - Draft Boulder Approved Tree and Plant List BOULDER FORESTRY APPROVED TREE LIST **DRAFT** July 2025

Species Name

Common Name

PROPERTY TYPE

Mature Mature Size Water Use Size (Height x Acceptable Cultivars (hydrozone) Category Spread in ft)

Mature Canopy Area (sq. ft)

Fall Color

Flowers

Pest/Abiotic Issues

Biodiversity / Pollinators / Habitat / Wildlife

Colorado Native (Yes/No)

Nectar for pollinators/ invertebrates (hoverfly,bees (honey bees, cellophane bees); hoverflies and ladybugs also go after aphids, small mammals, birds; shelter and nesting

2-inch caliper

1.5-inch caliper

Tolerates clay soil, air pollution, susceptible to winter dieback in early freezes; noted as invasive in NE US but very few specimens in Colorado so risk is low Not as drought tolerant as the tatarian maple; available in tree and shrub form

Yes

1.5-inch caliper

Prefers moist soils

Yes

2-inch caliper

1.5-inch caliper

Hazards / Toxicity

Minimum Size Category

Additional Notes

FIRE WUI AREAS

Approved for Private Approved for Public Approved for Parks Property (Yes/No) Street ROW (Yes/No) Properties (Yes/No)

SUBCOMMUNITY DIVERSITY

Approved for use in Approved for use in Central Boulder Approved for use in Approved for use in Approved for use in Approved for use in Approved for use in Approved for use in Approved for use in Approved for use in University Hill Palo Park Southeast Boulder Approved for Regulated Central Boulder Colorado University Crossroads East Boulder Gunbarrel North Boulder South Boulder WUI Areas IR1, IR2 and IR3 Subcommunity (Yes Subcommunity (Yes Subcommunity (Yes Subcommunity (Yes Subcommunity (Yes Subcommunity (Yes Subcommunity (Yes Subcommunity (Yes Subcommunity (Yes Subcommunity (Yes / No) in HIZ 5'-30' (Yes/No) / No) / No) / No) / No) / No) / No) / No) / No) / No)

DECIDUOUS TREE SPECIES

Acer campestre

Hedge maple

Acer ginnala

Ginnala maple

Queen Elizabeth

Low to Moderate

Medium

30 x 30

707

Yellow

Insignificant

Moderate

Small

15 x 15

177

Yellow to orange Insignificant to red

Acer glabrum

Rocky Mountain maple

Acer grandidentatum

Bigtooth maple

Acer griseum

Paperbark maple

Moderate

Small

Acer miyabe

Miyabe maple

State Street

Low to Moderate

Medium

30 x 30

707

Yellow

Insignificant

Acer negundo

Boxelder

For ROW, 'Sensation' is only acceptable boxelder

Low to Moderate

Large

40 x 40

1256

Yellow

Insignificant

Acer pseudoplatanus

Sycamore maple

Moderate

Large

35 x 30

707

Yellow

Insignificant

Rocky Mountain Glow

Low to Moderate

Small

20 x 15

177

Orange

Insignificant

Low

Medium

25 x 25

491

Orange, red

Insignificant

25 x 20

314

Orange, red

Acer saccharum

Sugar maple

Fall Fiesta, Legacy, Caddo

Moderate

Large

60 x 45

1590

Orange

Acer tataricum

Tatarian maple

Hot Wings, Pattern Perfect

Low to Moderate

Small

20 x 15

177

Red, yellow

Aesculus flava

Yellow buckeye

Moderate

Large

60 x 40

1256

Orange, yellow

Aesculus glabra

Ohio buckeye

Moderate

Medium

25 x 25

491

Orange to red

Aesculus glabra var. arguta

Texas buckeye

Low to Moderate

Medium

30 x 30

707

Yellow

Aesculus hippocastanum

Common horsechestnut

Aesculus x carnea

Red horsechestnut

Alnus glutinosa

European alder

Alnus incana ssp. tenuifolia

Thinleaf alder / Mountain alder

Amelanchier alnifolia

Western serviceberry

Amelanchier arborea

Downy serviceberry

Moderate

Briotti, Fort McNair

Saskatoon

Large

60 x 50

35 x 30

1964

707

Yellow

Moderate

Medium

Moderate to High

Medium

30 x 15

177

Yellow to brown

High

Small

40 x 40

1256

Yellow

Moderate

Small

10 x 8

yellow Shades of red, orange and yellow

Low to Moderate

Small

20 x 15

177

Orange, yellow

Amelanchier canadensis

Shadblow serviceberry

Amelanchier laevis

Allegheny serviceberry

Amelanchier utahensis

Utah serviceberry

Betula occidentalis

Water birch / Rocky Mountain birch

Moderate

Small

15 x 15

177

Yellow

Betula papyrifera

Paper birch

Moderate

Medium

30 x 15

177

Carpinus betulus

European hornbeam

Moderate

Medium

40 x 30

Carpinus caroliniana

American hornbeam

Moderate

Medium

30 x 30

Catalpa speciosa

Western / Northern catalpa

Celtis laevigata

Sugar hackberry

Snowcloud, Spring Flurry

Fastigiata, Frans Fontaine

All Seasons, Magnifica

Moderate to High

Small

20 x 15

177

Orange, yellow

Moderate

Small

15 x 15

177

Orange, yellow

Low to Moderate

Small

8 x8

Red

Insect pollinators, host for geometrid moths and winter moths, browse for large mammals, wetland indicator, seeds for small mammals, birds; shelter and nesting Host for leaf blotch miner moths, browse for large mammals, wetland indicator, seeds for small mammals, birds; shelter and nesting Nectar for bees and other pollnators; shelter and nesting

Insignificant

Insignificant Clusters of yellow-white flowers in the early spring Showy 6-inch panicles of creamy yellow flowers in the spring Showy creamy white to greenish yellow flowers in the spring Clusters of fragrant yellow to cream-colored flowers in the spring Spring flowering white-pinkish flowers Showy 8-inch panicles of pink or red coneshaped flowers in the spring Small purplishbrown catkins in early spring Small purplishbrown catkins in early spring Clusters of showy, white flowers

Nectar for bees and other pollinators; urban birds; shelter and nesting Special value to honey bees, host for cecropia silkmoth and geometrid moths; seeds and shelter for birds and other wildlife; shelter and nesting Nectar for bees and other pollinators; host for leaf miner moths, geometrid moths; shelter and nesting Some cultivars may develop chlorosis in alkaline soils

Prone to leaf scorch in hot and dry sites

1256

Yellow

Insignificant

Celtis occidentalis

Common hackberry

Low to Moderate

Large

50 x 50

1964

Yellow

Celtis reticulata

Netleaf hackberry

Low

Medium

30 x 30

707

Yellow

Crataegus mollis

Downy hawthorn

Crataegus rivularis Crataegus saligna

Crataegus succulenta

Low to Moderate

Small

15 x 15

177

Red to orange

Moderate

Small

20 x 15

177

Red

Low to Moderate

Small

20 x 15

177

River hawthorn

Moderate

Small

10 x 10

Willow hawthorn

Low to Moderate

Small

20 x 20

314

Fleshy hawthorn

Low to Moderate

Small

10 x 10

Green hawthorn

Winter King

Low to Moderate

Small

15 x 15

177

Purple to scarlet

Crataegus x mordenensis

Toba hawthorn

Toba

Low to Moderate

Small

15 x 15

177

Yellow

Fagus sylvatica

European beech

Purpurea, Tricolor

Moderate

Large

50 x 40

1256

Bronze

Gleditsia triacanthos inermis

Thornless honeylocust

For ROW, 'Shademaster' is the only approved cultivar

Low

Large

60 x 50

1964

Yellow

Gymnocladus dioicus

Kentucky coffeetree

Espresso, Stately Manor, Decaf

Low to Moderate

Large

60 x 50

1964

Yellow

Koelreuteria paniculata

Goldenrain tree

Low

Medium

35 x 35

962

Yellow

Liriodendron tulipifera

Tuliptree

Moderate

Large

60 x 35

962

Yellow

Maackia amurensis

Amur maackia

Moderate

Small

25 x 25

491

Yellow

Magnolia acuminata

Cucumbertree magnolia

Moderate

Large

55 x 30

707

Bronze, yellow

Magnolia Galaxy

Galaxy magnolia

Moderate

Small

25 x 15

177

Bronze

Magnolia x soulangiana

Saucer magnolia

Moderate

Small

25 x 25

491

Bronze

varies by cultivar

Malus sylvestris

Crabapple

Ostrya virginiana

American hophornbeam

Phellodendron amurense

Amur corktree

Only cultivars resistant to fireblight allowed in the ROW; Indian Magic, Prairiefire, Royal Raindrops, Spring Snow, Thunderchild

His Majesty, Macho, Eyestopper

Large

Moderate

Large

Populus deltoides ssp. monilifera

Plains cottonwood

Prunus cerasus

Sour cherry

Prunus maackii

Amur chockecherry

Montmorency

40 x 30

707

Yellow to brown

70-60

2827

Yellow to brown

Moderate

Large

70 x 60

2827

Yellow

Moderate

Small

15 x 15

177

Orange

Moderate

Small

20 x 20

314

Yellow

Prunus mandshurica

Manchurian apricot

Moderate

Small

15 x 15

177

Prunus padus

Mayday tree

Moderate

Small

20 x 20

314

Prunus pennsylvanica

Pin cherry

Moderate

Small

25 x 15

177

Prunus serotina

Black cherry

Moderate

Large

40 x 30

707

Prunus virginiana

Chokecherry

Ptelea trifoliata

Common hoptree

Sucker Punch, Canada Red Low to Moderate

Small

25 x 15

177

Very Low to Low

Small

20 x 20

314

Black willow

Moderate

Large

40 x 40

1256

Yellow

Scouler's willow

Moderate

Medium

30 x 30

707

Yellow

Sorbus aria

Whitebeam tree

Moderate

Medium

40 x 25

491

Bronze, yellow

Sorbus aucuparia

Mountain-ash

Moderate

Medium

30 x 15

177

Orange-red

Sorbus hybrida

Oakleaf mountain-ash

Moderate

Small

25 x 15

177

Sorbus scopulina

Greene's mountain-ash

Low to Moderate

Small

10 x 10

Bronze, red Brilliant orangered

Styphnolobium japonicum

Japanese pagoda tree

Cardinal Royal

Moderate

Large

50 x 50

1964

Yellow

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

Susceptible to fireblight

Host for catalpa sphinx moth, as well as tiger and geometrid moths; special value to honey bees; wetland indicator; shelter and nesting Nectar and pollen for bees (esp honey bees), host for Hackberry Emperor, American Snout, birds (inc. robins and songbirds) eat fruit; shelter and nesting Host for wild cherry sphinx, tawny emperor, American snout, question mark, mourning cloak butterflies; birds and mammals eat fruit; shelter and nesting Host for American snout, hackberry emperor, mourning cloak, birds and mammals eat fruit; wetland indicator; shelter and nesting Nectar and pollen for bees, special value to native bees esp bumble bees, nesting for native bees, nectar for butterflies and hummingbirds; seeds and flowerbuds eaten by birds Nectar and pollen for bumble bees and other long-tongued bees; shelter and nesting

Important larval and adult food source for many native invertebrates

Fewer disease issues Spring forage for bees (esp honey bees) Clusters of white than other and pollinating flies; fruit for birds, such flowers in spring hawthorns as robins; shelter and nesting Clusters of white flowers in spring Nuts for mammals and birds; shelter and Insignificant nesting 'Sunburst' can have Nectar for bees and butterflies; browse significant fungal for large mammals, host for silver spotted Insignificant canker issues skipper; shelter and nesting

Pollen for bumble bees and long-horned bees; shelter and nesting

Insignificant Showy panicles of golden yellow flowers in midsummer

Pollen and nectar for bees, esp. honeybees; shelter and nesting Abundant nectar and pollen for flies, beetles, honey bees, bumble bees, other long-tongued bees, hummingbirds; host for geometrid and saturniid moths; shelter and nesting

Showy yellowgreen large tulipshaped flowers in early summer Clusters of fragrant, white, pea-like flowers

Nectar and pollen for bees; shelter and nesting Pollinated by beetles and flies, possible host for black swallowtails; seeds for towhees and other ground-feeding birds; shelter and nesting Pollinated by beetles and flies, possible host for black swallowtails; seeds for towhees and other ground-feeding birds; shelter and nesting

Slightly fragrant, greenish-yellow tulip-like flowers Profusion of large, deep reddish-purple flowers Large saucershaped flowers in shades of purple, pink and white in the

Susceptible to several foliar fungal diseases Susceptible to several foliar fungal diseases

Hanging catkins in the spring before the leaves Individual white or pink flowers Dense racemes of fragrant creamy-white flowers

1.5-inch caliper

Tolerates clay soil, best used as multi stem tree Tolerates air pollution, wide range of soils, best used as multi stem tree

1.5-inch caliper

Yes

1.5-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

Best used as multi stem tree Available as tree or shrub form; best as a multi-stem tree; doesn't perform well in heavy clay soils Doesn't perform well in heavy clay soils Tolerates air pollution, dry sites, alkaline soils; protect from strong winds

Yes

2-inch caliper

Tolerates clay soil, alkaline soils, dry sites; needs a protected location

Yes

2-inch caliper

Tolerates drought once established, clay soil, and air pollution; fast growing

Yes

2-inch caliper

Yes

2-inch caliper

Tolerates clay soil, wet soil, air pollution Tolerates drought once established, clay soil, wet soil, and air pollution; can go dormant during summer months when drought stressed

Yes

2-inch caliper

Tolerates alkaline soil, drought.

1.5-inch caliper

2-inch caliper

1.5-inch caliper

2-inch caliper

Tolerates clay soil; needs a protected site; can be tree form or a multi-stem Protect from strong winds; fragrant creamy white flowers on pendulous 8-14" long panicles; susceptible to sunscald

Thorns

1.5-inch caliper

Yes No

Thorns Thorns except for the thornless variety (var. inermis)

1.5-inch caliper

Yes

Thorns

1.5-inch caliper

Best grown as a multi-stem tree / shrub Tolerates drought once established and most soils except heavy clay; very nice pyramidal shape; very drought tolerant Very drought tolerant, clay soils, and dry soils; has thorns; good replacement for native hawthorns in urban landscapes because fewer disease issues; can be grown as a single or multi-stem tree Can be grown as a single or multistem tree Can be grown as a single or multistem tree Can be grown as a single or multistem tree

Thorns

1.5-inch caliper

Thornless; can be grown as a single or multi-stem tree

Thorns

1.5-inch caliper

Thorns

1.5-inch caliper

Yes

Thorns

1.5-inch caliper

Yes

Thorns

1.5-inch caliper

Has thorns; can be grown as a single or multi-stem tree Tolerates alkaline soils, clay soils; has thorns; can be grown as a single or multi-stem tree Can be grown as a single or multistem tree Can be grown as a single or multistem tree

Yes

Wildlings will have long, sharp thorns

2-inch caliper

Do not consume - plant parts may be poisonous

2-inch caliper

Can be grown as a single or multistem tree Tolerates drought, clay soils, and dry soils; has thorns; holds fruit all winter; can be grown as a single or multi-stem tree Can be grown as a single or multistem tree Intolerant of wet, poorly drained soils Tolerates drought once established, clay soil, and air pollution Tolerates drought once established, air pollution; Decaf and Espresso are essentially podless

1.5-inch caliper

Tolerates drought, clay soil, air pollution; can seed profusely

Yes

2-inch caliper

Tolerates clay soil, wet soil

Yes

1.5-inch caliper

Adapts to a wide range of soils

Yes

2-inch caliper

Intolerant of most urban pollutants

Yes

Thorns

1.5-inch caliper

May have some thorns but not as many as other hawthorn species

1.5-inch caliper

Thorns

1.5-inch caliper

2-inch caliper

1.5-inch caliper

Protect from strong winds; can be grown as a single or multi-stem tree

Yes

1.5-inch caliper

Tolerates clay soil; can be grown as a single or multi-stem tree

Yes

1.5-inch caliper

Yes

2-inch caliper

Shelter and nesting

2-inch caliper

Important larval food source for many native invertebrates

Yes

2-inch caliper

Important larval food source for many native invertebrates

Yes

2-inch caliper

Yes

2-inch caliper

Nectar and pollen for bees (esp. honey bees) and fruit for songbirds and small mammals; shelter and nesting

Special value to native bees; host for western tiger swallowtails; fruit for songbirds and mammals; shelter and nesting Pollinated by carrion flies; host for twotailed and western tiger swallowtails, shelter and nesting

Susceptible to oak rough bullet gall wasp - choose gallless tree stock for parks & ROW as galls may attract

Short lived; cannot withstand prolonged drought Tolerates clay soil, soil compaction, best used as multi stem tree

Seeds for towhees and other groundfeeding birds; shelter and nesting

Important larval food source for many native invertebrates

Insignificant

Salix scouleriana

Yes

Bronze

Salix nigra

Yes

1964

Yellow

Yes

40 x 50

Yellow

Yes

Large

Yes

Low to Moderate

707

Yes

Insignificant

10 x 10

Yes

Bronze

35 x 30

Yes

3848

Small

Yes

70 x 70

Large

Yes

Large

Moderate

Yes

Low to Moderate

Moderate

Yes

Insignificant

Bebb willow

Yes

Bronze, red

Peachleaf willow

Yes

1964

Salix bebbiana

Yes

50 x 50

Salix amygdaloides

Yes

Insignificant

Insignificant Yellow-green catkins Yellow-green catkins Yellow-green catkins Yellow-green catkins Clusters of white flowers Clusters of white flowers Clusters of white flowers Clusters of white flowers Fragrant greenwhite to yellow flowers in midsummer

Yes

Large

Yellow

Yes

Insignificant

Yes

Insignificant

10 x 10

Yes

Bronze

Small

Yes

Bronze, orange

Very Low to Low

Yes

314

Wavy-leaf oak

Yes

Spring display of Golden-orange pink flowers Dense racemes of fragrant creamy-white Yellow flowers Clusters of white Yellow to red flowers Dense racemes of fragrant Yellow to orange creamy-white to red flowers Dense racemes of fragrant creamy-white Yellow flowers Sprays of tiny star-shaped Yellow greenish-white

Quercus undulata

Yes

2376

Chinkapin oak

Yes

55 x 55

Quercus muehlenbergii

Yes

20 x 20

Bulletproof

Yes

Large

Bur oak

Yes

Small

Quercus macrocarpa

Yes

Insignificant

Moderate

Yes

Red

Shingle oak

Yes

Deep purple to red

Quercus imbricaria

Yes

314

Moderate

Intolerant of drought

3318

Very Low to Low

Yes

2-inch caliper

30 x 20

Gambel oak

Yes

2-inch caliper

65 x 65

Swamp white oak

2-inch caliper

Large

Quercus gambelii

Yes

Medium

Quercus bicolor

Tolerates alkaline soils, road salts

Low to Moderate

White oak

2-inch caliper

Yes

Cleveland Select, Chanticleer, Autumn Blaze Low to Moderate

Flowering pear

Quercus alba

Yes

Important larval food source for many native invertebrates

Abundant , fivepetaled flowers in early spring known for their Moderately resistant unpleasant odor to fireblight

Pyrus calleryana

Yes

Yellow

Moderate

Yes

491

Eastern cottonwood

Yes

1590

Narrowleaf cottonwood

Yes

Intolerant of drought

30 x 25

Populus deltoides

Yes

2-inch caliper

40 x 45

Populus angustifolia

Yes

Do not consume - plant parts may be poisonous

Large

Yellow

Yes

Do not consume - plant parts may be poisonous

Small

707

Yes

Medium

50 x 30

Yes

Nectar for hummingbirds, bees (esp. honey bees); shelter and nesting

Moderate

Large

Yes

Low to Moderate

Moderate

Yes

Low to Moderate

Lanceleaf cottonwood

Yes

Important to select a cultivar with good to excellent resistance to the following: fireblight, scab, cedar apple rust, and Varies by cultivar mildew; only Pollen and nectar for bees, esp. honey Mainly yellow but typically fragrant resistance cultivars bees; host for geometrid and leaf miner can vary by clusters of white allowed on public moths; some have seeds for birds and cultivar to pink flowers mammals; shelter and nesting property Seeds for songbirds and small mammals; Yellow Insignificant wetland indicator; shelter and nesting

Populus x acuminata

Yes

Prone to leaf scorch in hot and dry sites

Insignificant

Insignificant Hanging catkins in the spring before the leaves Hanging catkins in the spring before the leaves Hanging catkins in the spring before the leaves

Tolerates clay soil, drought once established, air pollution, alkaline soils

Prone to leaf scorch in hot and dry sites

Clusters of white Good resistance to Red flowers in spring fireblight Yellow, orange or Clusters of white red flowers in spring Clusters of white Yellow to orange flowers in spring Shades of red, Clusters of white orange and flowers in spring purple

Crataegus viridis

Yes

2-inch caliper

Yes

Spring forage for bees (esp honey bees) and pollinating flies; fruit for birds, such as robins; shelter and nesting

Crimson Cloud, Paul's Scarlet

Yes

2-inch caliper

Yes

Clusters of bright white flowers in Good resistance to fireblight early spring Clusters of white flowers in spring Clusters of white flowers in spring Clusters of white flowers in spring All cultivars are Clusters of white susceptible to flowers in spring fireblight All cultivars are Clusters of white susceptible to flowers in spring fireblight

Lavalle hawthorn

Yes

Mammals eat seeds; shelter and nesting

English hawthorn

Yes

Insignificant

Crataegus lavellei

Yes

Bronze

Crataegus laevigata

Yes

707

Yellow to red

Yes

45 x 30

Red Orange to red to purple-red

Yes

Medium

Orange

Yes

Low to Moderate

Yes

Turkish filbert

177

Yes

2-inch caliper

Corylus colurna

177

Do not consume - plant parts may be poisonous

Yellow

177

Yellow

8 x 10

Yes

Nectar for hummingbirds, bees (esp. honey bees); host for dagger moths and geometrids; shelter and nesting

Yellow

20 x 15

Yes

177

10 x 15

Yes

491

20 x 15

Yes

Tolerates alkaline soil, drought once established Tolerates clay soil, intolerant of drought, protect from strong Tolerates wet sites, but prefers acidic soils; limited availability at nurseries

Yes

1256

Small

Yes

10 x 15

Small

Yes

40 x 40

Small

Yes

25 x 25

Small

Yes

Small

Moderate

Yes

Small

Moderate

Yes

Medium

Very Low to Low

Yes

Moderate

Low to Moderate

Yes

Moderate

Thornless

Moderate

Cerro hawthorn

Yes

Cornelian cherry dogwood

Cockspur hawthorn

Yes

2-inch caliper

Yellowwood

Fireberry hawthorn

Do not consume - plant parts may be poisonous

Eastern redbud

Russian hawthorn

Yes

Cornus mas

Crataegus erythropoda

Yes

Nectar for hummingbirds, bees (esp. honey bees); host for dagger moths and geometrids; shelter and nesting

Cladrastis kentukea

Crataegus crus-galli

Yes

Intolerant of drought; prefers acidic soils

Cercis canadensis

Crataegus chrysocarpa

Yes

2-inch caliper

Striking pink to purple flowers in early spring Fragrant, white, Wisteria-like racemes in early summer Clusters of bright yellow flowers in early spring

Crataegus ambigua

Yes

Do not consume - plant parts may be poisonous

Shelter and nesting Host for striped hairstreak; mammals and birds (including warblers, grouse and pheasant) eat seeds; shelter and nesting; host for eastern tiger swallowtail

45 x 40

Yes

Insignificant

Medium

Yes

2-inch caliper

Orange, red

Low to Moderate

Yes

1.5-inch caliper

Yellow

Yes

707

50 x 30

Yes

Nectar for bees, butterflies, hummingbirds and other pollinators, host for leaf miner and tiger moths, seeds for small mammals; shelter and nesting

Yellow

Large

Yes

Nectar for bees and other pollinators

Important larval food source for many native invertebrates

Low to Moderate

Yes

Intolerant of soil compaction, road salts, air pollution Tolerates soil compaction, clay soil; available in tree and shrub form; 'Hot Wings' may sustain storm damage due to heavy seed set

Yellow to brown catkins Yellow to brown catkins

Insignificant Showy clusters of large white orchid-like flowers in late spring / early summer

Yes

Special value to honey bees; shelter and nesting

White, 5-petaled flowers Showy, slightly fragrant, white flowers in drooping Small, slightly fragrant flowers Clusters of white, rose-like

Yes

Nectar and pollen for insects (bees, flies); fruit for songbirds and small mammals; shelter and nesting Honey bees may visit oak gall honeydew; host for geometrid, tiger, leaf miner and other moths; acorns for birds and small mammals; shelter and nesting Honey bees may visit oak gall honeydew; host for geometrid, tiger, leaf miner and other moths; acorns for birds and small mammals; shelter and nesting Host for purple hairstreak (CO state butterfly) geometrid, tiger, leaf miner and other moths; acorns for birds and small mammals; shelter and nesting Honey bees may visit oak gall honeydew; host for geometrid, tiger, leaf miner and other moths; acorns for birds and small mammals; wetland indicator; shelter and nesting

Honey bees may visit oak gall honeydew; host for geometrid, tiger, leaf miner and other moths; acorns for birds and small mammals; shelter and nesting Honey bees may visit oak gall honeydew; host for geometrid, tiger, leaf miner and other moths; acorns for birds and small mammals; shelter and nesting Honey bees may visit oak gall honeydew; host for geometrid, tiger, leaf miner and other moths; acorns for birds and small mammals; shelter and nesting

Susceptible to fireblight

Susceptible to fireblight Important adult and larval food source for many native invertebrates Host for pyralid moths; nectar and pollen for bees and other insects; shelter and nesting

Yes

2-inch caliper

1.5-inch caliper

Tolerates air pollution, adapts to a wide range of soils. Tolerates drought once established, clay soil Tolerates drought once established

Suckers profusely

Former scientific name was Populus sargentii ; often sold in nurseries as a substitute for Eastern cottonwood

Excellent cold hardiness Seldom produuces fruit so makes a good street tree; drought tolerant; longer lived Prunus sp

Yes

Yes Yes

Yes

1.5-inch caliper

Yes

1.5-inch caliper

Yes

2-inch caliper

Yes

1.5-inch caliper

Yes

1.5-inch caliper

2-inch caliper

Tolerates drought, dry soil, shallow and rocky soil; 'Sucker Punch' does not produce suckers Tolerates drought once established, dry soil; weakwooded Tolerates drought, clay soil, air pollution; prone to breakage in snowstorms; Noted as invasive in eastern US, as well as CA, UT, NM however rarely produces fruit in CO so risk is low

2-inch caliper

Tolerates drought once established, clay soil, dry soil, shallow and rocky soil

Yes

2-inch caliper

Yes

1.5-inch caliper

Tolerates drought once established, wet soil Available in tree and shrub form; best used as multi-stem; can tolerate extreme heat and cold temperatures

2-inch caliper

Tolerates drought once established, adapts to a wide variety of soils

Yes

2-inch caliper

Tolerates drought once established, clay soil, dry soil

Yes

2-inch caliper

Hard to establish; tolerates drought once established

Yes

1.5-inch caliper

Best used as multi-stem tree/shrub; may hold onto leaves all winter

Yes

Yes Yes

2-inch caliper

Yes

1.5-inch caliper

Yes

2-inch caliper

Yes

2-inch caliper

1.5-inch caliper

Yes

1.5-inch caliper

2-inch caliper

Tolerant of all soil types Extremely cold hardy; dark green foliage is silvery underneath Intolerant of road salts; tolerant of all soil types

Tough tree; good substitute for flowering pears in landscapes; tolerates drought once established, air pollution

Yes

Attachment C - Draft Boulder Approved Tree and Plant List Syringa pekinensis

Chinese tree lilac

China Snow

Moderate

Small

20 x 15

177

Bronze, yellow

Syringa reticulata

Japanese tree lilac

Ivory Silk

Moderate

Small

25 x 15

177

Yellow

Large clusters of creamy-white, fragrant flowers Large clusters of creamy-white, fragrant flowers

Tilia americana

American linden

Boulevard, Legend, Frontyard, American Sentry, Redmond

Fragrant yellow flowers in the spring

Tilia cordata

Tilia tomentosa

Tilia x flavescens

Moderate

Large

60 x 40

1256

Yellow

Littleleaf linden

Moderate

Medium

35 x 35

962

Yellow

Silver linden

Moderate

Large

50 x 30

707

Yellow

Glenleven linden

Moderate

Large

40 x 40

1256

Yellow

Ulmus americana

American elm

*check with Boulder Forestry for approved varieties and cultivars

Ulmus davidiana

David elm

Choice City

Ulmus davidiana var japonica 'Morton'

Accolade elm

Xanthoceras sorbifolium

Golden yellowhorn

Varies

Clear Creek

Low to Moderate

Large

70 x 50

1964

Yellow

Insignificant

Moderate

Medium

45 x 45

1590

Yellow

Insignificant

Low to Moderate

Large

55 x 35

962

Yellow

Insignificant

Yellow

Very showy white flowers in May

Very Low to Low

Small

Fruit trees

Moderate to High

Varies

white fir

Moderate

20 x 15

177

Varies

CONIFEROUS TREE SPECIES Abies concolor

50 x 25

688

Large Cedrus atlantica

atlas blue cedar

Low to Moderate

Small

Larix decidua

European larch

Moderate to High

Large

50 x 25

625

dawn redwood

Moderate

Large

85 x 20

850

white spruce

Moderate

Large

50 x 15

375

Picea pungens

blue spruce

Low to Moderate

50 x 30

375

Large

Low to Moderate

bristlecone pine

Pinus edulis

pinyon pine

Pinus flexilis

limber pine

Pinus ponderosa

Ponderosa pine

Low

Pinus strobiformis

southwestern white pine

Low

30 x 15

25 x 20

263

40 x 35

750

70 x 35

1125

50 x 30

1350

Medium

Very Low Medium Vanderwolf' not allowed (does not perform well in Low Colorado)

Large

Rocky Mountain Douglas-fir

Sequoiadendron giganteum

giant sequoia

Low to Moderate

50 x 20

688

40 x 30

2000

Large

Moderate Large

Taxodium distichum

baldcypress

Use only straight genus/species - o Moderate to cultivars allowed in city High parks & ROW

Varies

1.5-inch caliper

Can be grown as a single or multistem tree Tolerates clay soil, urban conditions; can be grown as a single or multi-stem tree

2-inch caliper

Tolerates drought once established

2-inch caliper

Yes

2-inch caliper

Shelter and nesting

2-inch caliper

Shelter and nesting

2-inch caliper

Nectar and pollen for insects, esp. bees

1.5-inch caliper

Nectar and pollen for insects, esp. bees

Varies

1.5-inch caliper

Host for geometrid, tortricid and owlet moths; seeds for songbirds and small mammals; deer, porcupines feed on foliage and bark; shelter and nesting

Yes

5-foot height

Shelter and nesting

Shelter and nesting Forage for many mammals; shelter and nesting Increased susceptibility to Ips beetle post Host for geometrid, tiger moths; forage construction or if irrigation insufficient for many mammals; shelter and nesting Host for tortricid moth; seeds feed many birds (turkeys, nuthatches, grosbeaks, crossbills) and mammals (chipmunks, squirrels); large mammals (deer, porcupines, elk) graze on needles;nesting and shelter Host for geometrid, tiger, satyr, and Increased tortricid moths; seeds feed many susceptibility to pitch mammals and birds including turkeys, mass borer in jays, rodents, deer, bears; shelter and irrigated sites nesting Host for geometrid, tortricid moths and western pine elfin; seeds feed many mammals and birds; shelter and nesting Host for pine white and pandora pinemoth, as well as geometrid, owlet, and tortricid moths; seeds feed many birds (turkeys, nuthatches, grosbeaks, crossbills) and mammals (chipmunks, squirrels); large mammals (deer, porcupines, elk) graze on needles;nesting and shelter Host for tortricid moth; seeds feed many birds (turkeys, nuthatches, grosbeaks, crossbills) and mammals (chipmunks, squirrels); large mammals (deer, porcupines, elk) graze on needles and bark;nesting and shelter Host for pine white and geometrid moths; seeds feed many birds (chickadees, finches, grosbeaks, crossbills) and mammals (chipmunks, squirrels); large mammals (deer, porcupines, elk, beaver, rabbits) graze on needles;nesting and shelter

1050

Seeds for birds and small mammals; shelter and nesting

Yes

Tolerates drought one established Better heat tolerance than other linden species; not tolerant of deicing salts

Tolerates drought once established Tolerates drought once established; similar vase shaped form of American elm but smaller statured; should be pruned in youth to develop good structure

Tolerates drought once established Tolerates drought one established, adaptable to a wide range of growing conditions; best grown as a multi-stem tree / shrub Fruit trees for food production are prohibited on properties west of Broadway Avenue to protect wildlife by reducing the incidence of encounters with bears in urban areas.

Yes

Prefers moist, acidic soils

5-foot height

5-foot height Yes

5-foot height

Yes

5-foot height

Drought tolerant once established, protect from strong winds

Tolerates clay soil, air pollution, wet soil Very cold hardy, sensitive to road salt and air pollution

Yes

Tolerates drought, air pollution

Tolerates poor, rocky soils, and alkaline soils; not vey drought tolerent Yes

5-foot height

Yes

5-foot height

Tolerates drought

Yes

5-foot height

Adaptable to a wide variety of soils

Tolerates drought

Yes

5-foot height

Yes

5-foot height

Prefers moist soils but can withstand drought

Prefers moist soils but can withstand drought Yes

Nesting and shelter 50 x 25

Large

Resistant to elm leaf beetles & Dutch elm disease Resistant to elm leaf beetles, European elm scale & Dutch elm disease

5-foot height

Picea glauca

Pinus aristata

Varies

Spring forage for bees, butterflies, hummingbirds; shelter and nesting Spring forage for bees, butterflies, hummingbirds; host for blinded sphinx moths, mourning cloak and question mark butterflies; associated with firefly habitat (attracts prey); shelter and May see minor nesting - mature trees may have cavities defoliation from for wood ducks, woodpeckers, and other Japanese beetle species Spring forage for bees, butterflies, hummingbirds; host for blinded sphinx moths, mourning cloak and question mark butterflies; associated with firefly habitat (attracts prey); shelter and nesting - mature trees may have cavities May see defoliation for wood ducks, woodpeckers, and other from Japanese beetle species Nectar and pollen for native bees and honey bees, nectar for butterflies; shelter and nesting May see minor defoliation from Japanese beetle Choose a Host for mourning cloak, question mark, variety/cultivar painted lady; seeds for birds; shelter and resistant to Dutch nesting elm disease

60 x 25

Metasequoia glyptostroboides

Pseudotsuga menziesii var. glauca

Fragrant yellow flowers in the spring Fragrant yellow flowers in the spring Fragrant yellow flowers in the spring

Resistant to powdery Spring forage for bees, butterflies, mildew hummingbirds; shelter and nesting

5-foot height

Intolerant of clay soils, prefers moist, well drained soils; protect from drying winter winds; specimens in northern city parks have been heavily

Tolerates clay soil, air pollution Yes

5-foot height

Attachment C - Draft Boulder Approved Tree and Plant List Scientific Name

Amelanchier alnifolia

Amelanchier utahensis

Approved in Regulated Boulder WUI HIZ 5- Designated County native wetland Common Name 30 ft Context

Saskatoon serviceberry

Utah serviceberry

Amorpha canescens

Leadplant

Amorpha fruticosa var. angustifolia

False indigo

Amorpha nana

Arctostaphylos uva-ursi

Arctostaphylos x coloradensis

Aronia melanocarpa

Kinnikinnick

Campsis radicans

Trumpet creeper

Ceanothus americanus

New Jersey tea

White

Apr-Jun

50007000

6’

White

May-Jul

Residential, Parks, Urban,

35007500

Full sun

Low

Welldrained rocky or sandy soils

3-6'

Purple

May-Jul

Parks, Native plantings

60008000

Full sun

dry sands or clay Moderate loam, pH adaptabl 3-15' -High

5-15'

Purple

Apr-Jun

Residential, Parks, Urban

500010000

Residential, Parks, Urban

Parks, Ag buffers, Native plantings

Residential Residential, Parks, Urban

Buckbrush/ Mountain lilac

Western redbud Y

50008125

50006200

50007000

Clay, loam, Full sun- Moderate sandy, gravelly 2-3' part sun low Acidic soil (pH<6.8), dry, moist. rocky or sandy soil, excellent Full sundrainage 1' part sun Low

Full sun- Moderate Loam, sandy part sun low

Full sunAcidic, part sun Moderate moist

Full sun

Cotoneaster adpressus

Creeping cotoneaster

Cylindropuntia spp.

Ephedra viridis

Ericameria nauseosa ssp. nauseosa

Ericameria nauseosa

Fallugia paradoxa

Fendlera rupicola

Forestiera pubescens Gutierrezia sarothrae

Hesperaloe parviflora

Cholla

Y Y

Mormon tea

Dwarf blue rabbitbrush

Tall green rabbitbrush

Canyon plume

Cliff fendlerbush

Desert olive Broom snakeweed

Red yucca

Residential, Parks, Urban, Ag buffers, Native plantings

50008000

Residential, Parks, Urban

50006500

Residential, Parks, Urban

50006500

Residential, Native plantings

50006000

Residential, Parks, Urban

50006200

Residential, Parks, Urban, Ag buffers, Native plantings

50008000

Parks, Ag buffers, Native plantings

50008000

Residential, Urban

50007500

Residential, Parks, Urban

50008000

Residential, Parks Parks, Urban, Ag buffers, Native plantings

50008000 5000 7500

Residential, Parks, Urban

Full sun-

50006000

Well-

Moderate drained

Moist, well drained Full sunshade High-low soils

5’

Pink

White

May

Apr-Jul

Variable-shaped shrub covered with dense silvery hairs - may be rounded or sprawling; female plants have showy winged fruits

Prune in late winter or early spring, cutting branches back to 3-4 buds to promote compact growth

Nectar for hummingbirds and other longtongued pollinators; deer/rabbit resistant

Self-clinging woody climber with shiny pinnate leaves and trumpet-shaped flowers Trellises or cottage gardens

drought but has difficulty transplanting

Nectar for hummingbirds, butterflies, bees and other long-tongued pollinators

Compact, rounded shrub with toothed, oval dark green leaves and cylindrical clusters of fragrant flowers

Plantings on slopes, pollinator gardens

Shear for compact growth

Forage for pollinators and biocontrol; special value to native bees; host for duskywings, metalmark butterflies; shelter and nesting for birds and small mammals

Thorny evergreen shrubs with bluish-gray branches, blooms profusely

Open valleys, hillsides & woods, understory plantings in residential and parks, rock gardens

Pruning is minimal; water young trees regularly but overwatering can lead to root rot

Forage for generalist bees and butterflies, as well as hummingbirds; deer/rabbit resistant

Shrub or small tree with rounded crown and alternate round leaves; showy pea-like flowers appear before leaves emerge

Accent tree, street tree

Nitrogen fixer

Prune lightly in late winter for a bushier shrub, deadhead if desired

Forage for bees, wasps, and flies, especially attractive to bumble bees; cover for urban birds

Upright, semi-evergreen shrub with ferny foliage and terminal clusters of flowers and attractive seedheads

Parks, residential, urban core, streetscapes

Tolerates deer and rabbits; PlantSelect

support for climbing; pruning needs depend on flowering

Forage for generalist bees; deer/rabbit resistant

Rambling vine with showy, star-shaped flowers

Trellises or cottage gardens

Berries and perches for over 98 spp of birds including flickers, tanagers, woodpeckers and catbirds; , mammals, butterflies and birds. Larval host of the Spring Azure.

Upright and spreading deciduous shrub with attractive glossy leaves and red bark, terminal clusters of tiny flowers

check sp. name; tolerates deer and rabbits; syn. Swida sericea ; cultivar Erosion control, shrub beds, 'Kelseyi' is dwarf and pollinator gardens, riparian buffers; has higher fire winter interest; resistance score (6)

Low

Clayalkaline soils, well drained

Full sun

Low

Gravelly, sandy, dry, welldrained soil 4-6'

Full sun

Dry, rocky, welldrained, poor, Very low alkaline

Full sun

Low

Full sun

Very low Dry

Yellow

AugustOctober

Shelter and nesting for birds and mammals

China

Low maintenance

Cover and protection; forage for generalist bees

Pink, white

Apr-Jun

Adaptabl e 12'

Insignific ant Apr-May

Yellow

Aug-Nov Y

Jun-Aug

Y Y

Pink

Prune very lightly in spring if bloom is desired

Ocean spray

Parks, Ag buffers, Native plantings

Full sun- Highmoderate Moist

6-20'

10-15'

White

Rock spiraea

Residential, Parks, Ag buffers, Native 6200plantings 8000

Full sun part shade Low

May-Aug Y

Holodiscus dumosus

3-6'

White

Jun-Aug

Jamesia americana

Waxflower

Residential, Parks, Urban, Native plantings

Full sun- Moderate -low shade Loam

White

May-Jun Y

Clay, chalky, or sandy alkaline Very low soils, 3'

White

May-Jul

Krascheninnikovia lanata

Lonicera involucrata

Winterfat

Twinberry

5000-700 shade

50008000

Parks, Ag buffers, Native plantings

50007000

Full sun

Residential, Native plantings

60008000

Average, welldrained, organical Full sunpart sun Moderate ly rich 10'

Woodbine

Mahonia aquifolium

Compact Oregon Grape

Mahonia repens

Creeping Oregon grape

Malus sargentii

Sargent crabapple

Opuntia macrorhiza

Prickly pear cactus

Opuntia polyacantha

Prickly pear cactus

Residential Residential, Parks, Urban

20' 5000-600 part sun Moderate y rich 5000Part sun to shade Low 7000 Acidic, we 6'

Residential, Parks, Urban

50007500 ft

Residential, Parks, Urban

50007000 ft

Full sun

Moist humus rich soils, Moderate well drained 4' low Welldrained acidic loams but Moderate adaptabl 8'

Residential, Ag buffers, Native plantings

5000 6000 ft

Full sun

Dry acidic, rocky or sandy Very low soils

Full sun

Dry, clay loams or rocky Very low soils 1'

Residential, Ag buffers, Native plantings

5000 6000 ft

Full sun to part sun

Yellow

Virginia creeper

Residential, Urban

Full sun adaptabl 50' 5000-950 shade Moderate e

Philadelphus lewisii

Cheyenne mock orange Y

Residential, Parks, Urban

50008125 ft

Philadelphus microphyllus

Little-leaf mockorange

Residential, Parks, Urban

5000 9000 ft

Clay, loam, sand

Erosion control, hedges, upland plantings, natural areas, prairie buffers

Tolerates deer and rabbits

Do not shear - cut oldest woody stems to ground to rejuvenate and remove suckers

Semi-evergreen multi-branched shrubs with small olive-green leaves. 5-petaled flwoers with yellow stamens turn into feathery pink plumes.

Erosion control, xeric landscapes, streetscapes, pollinator gardens, shrub beds

Tolerates deer and rabbits; note change from Apache plume to Canyon plume

Lankiness is Browse for large mammals; forage for improved by pruning pollinators

deciduous; Small, grayish-green narrow leaves with edges rolled under; white to pink flowers, bark reddish-tan; Deciduous shrub with arching branches and small oval leaves; flowers lack petals and aren't very showy but result in dark blue berries

Prune for size and health as needed

do not overwater

Pollen and nectar for many pollinators, especially mid-sized or small bees

Berries for birds; shelter and nesting for birds, mammals, invertebrates Late season forage for flies, beetles, and solitary bees; seeds for birds

Sub-shrub with many branching stems and thread-like green leaves

less available

Upland plantings, natural areas, streetscapes and medians

A xeric, long-blooming, very low maintenance evergreen that forms a dense clump of narrow, leathery, arching gray-green leaves. Xeric and pollinator gardens in urban core, residential, industrial, Slender branched flower spikes bear many red, tubular flowers on long erect scapes that and parks; large container plantings are twice the height of the foliage.

Tolerates deer and rabbits

Winter interest due to plant habit; tolerates deer;

Don't overwater

Nectar for hummingbirds as well as other long-tongued pollinators

Seeds require cold stratification (less than 41 degrees) up to 18 weeks

Host plant for spring azure, swallowtail and Lorquins admiral butterflies. Visited by bees (bumble and sweat); special value to native bees; good shelter for birds

Spreading shrub with slender stems and toothed leaves; blooms profusely in plumed clusters

Bioswale; disturbed land; wetland indicator

Browse for mammals; forage for many pollinators; cover and protection

Low deciduous shrub with reddish twigs feathery clusters of small flowers

Understory plantings, shrub borders in residential and park areas

Syn. Holodiscus discolor var. discolor Syn. Holodiscus discolor var. dumosus

Low maintenance; prune dead wood as Cover and protection; seeds for birds; needed forage for pollinators

Rounded deciduous shrub with flaking bark, clusters of fragrant waxy flowers and textured leaves with bright autumn color

Pollinator gardens in parks and residential areas; shrub plantings, dry, rocky open slopes, hills and ridges

Fragrant flowers

Must have male plant nearby to produce Cover and protection for birds and fruits mammals

Low spreading deciduous shrub with fuzzy bluish leaves; flower clusters become fluffy like lamb's tails;

Upland plantings and natural areas, buffers

syn. Ceratoides lanata

Low maintenance; may naturalize to form colonies