Narrowleaf Cottonwood

Populus angustifolia

Salicaceae · broadleaf deciduous tree · introduced

Last updated

Populus angustifolia (Salicaceae) is a deciduous tree native to the mountains and stream corridors of western North America. It grows 50 to 70 feet tall with a narrow, upright crown and slender, willow-like leaves (narrower than other cottonwoods). The bark is smooth and greenish on young trees, becoming gray and furrowed with age.

Narrowleaf cottonwood is a riparian species that colonizes stream banks and moist mountain valleys at moderate to high elevations. It grows rapidly in full sun with ample moisture. Like all cottonwoods, female trees produce abundant cotton-like seed floss. Hardy in Zones 3a to 8b.

Plant Profile

Size & Form

Height
50–65 ft
Spread
35-45 ft
Growth Rate
Fast
Size at 20 yr
60 ft
Lifespan
Moderate

Site Requirements

Light
Full Sun
Soil Drainage
Wet Tolerant
Soil pH
6.0-7.5
Water
High
Drought Tolerance
Low
Hardiness
Zones 3a–8b

Ornamental Interest

Bloom Time
spring
Fall Color
Yes
Origin
Pacific Northwest native
Watch for this season

Peak Spore Production and Dispersal

Active Conidial Spread

AphidHigh

Peak Population & Dispersal

Larval Feeding & Web Building

+ 7 more — see full disease and pest lists below

Diseases: Regionally Documented (17)

Pests: Regionally Documented (14)

Phenological Calendar

View full calendar (7 stages)
Stage Typical Window
Bud break BBCH 07 May 15-Jun 15
Leaf emergence BBCH 11 Jun 1-Jul 1
Bloom start BBCH 61 Mar 15-May 15
Bloom end / petal fall BBCH 69 Apr 15-May 31
Fruit/seed development BBCH 71 Jun 1-Aug 31
Fall color / leaf senescence BBCH 93 Oct 1-Nov 15
Dormancy BBCH 97 Nov 15-Feb 28
Data Maturity
Structured Multiple sources. Expert review underway.