Populus trichocarpa
Black cottonwood
Photo by Chez Brungraber
Family: Salicaceae · Type: Tree · Native
Populus trichocarpa (Black cottonwood) is a native California tree in the Salicaceae family, recognized by largest size, ovate glaucous leaves, and very resinous ciliate buds.
Black cottonwood is a native tree found in California's Foothill Woodlands and Great Basin bioregions along alluvial bottomlands and streamsides at elevations of 5 to 3,050 meters. Flowering from February to April, this tree produces flowers with subtle coloration characteristic of its species. Growing up to 30 meters tall with a wide, spreading crown, it features brown twigs that turn gray with age and remarkably fragrant, resinous winter buds. Its distinctive leaves are 3 to 7 centimeters long, ranging from narrowly to widely ovate, with a green upper surface and glaucous lower surface often stained with brown resin, featuring finely scalloped margins and rounded to heart-shaped bases. The tree's winter buds are especially notable for being finely ciliate and releasing a distinctive fragrance when they open.
Identification and appearance
Key characters: 5 sympatric species; largest size, ovate glaucous leaves, and very resinous ciliate buds are diagnostic
Habitat and range
Habitat: Scattered. Alluvial bottomland, streamsides
Elevation: 5-3050 m
California counties: Los Angeles, Ventura, San Bernardino, Santa Barbara, Kern, Riverside, El Dorado, Tulare, Inyo, Plumas, Sierra, Stanislaus, Mono, Fresno, San Luis Obispo, Mariposa, Orange, Humboldt, Placer, San Mateo, Siskiyou, Santa Clara, Madera, Sonoma, Monterey, San Diego, Santa Cruz, Lassen, San Benito, Modoc, Nevada, Shasta, Del Norte, Mendocino, Contra Costa, Tuolumne, Alameda, Alpine, Tehama, Butte, Trinity, Lake, Amador, Napa
Outside California: to Alaska, northern Rocky Mountains, Utah, northern Baja California
Bloom period
Populus trichocarpa blooms Feb-Apr.
How to tell it apart
vs Quercus: Poplar leaves flutter conspicuously on flat petioles; oaks have stiff leaves that don't flutter and produce acorns.; vs Salix: Poplar catkins hang downward like tassels; willow catkins stand upright or spread outward.; vs Pyrus: Poplars have catkins and cottony seeds; pears have showy white flowers and round pear-shaped fruits.; vs Platanus: Poplar bark is furrowed; sycamore bark peels in puzzle-piece patches revealing white inner bark.; vs Alnus: Poplar catkins are soft and pendulous; alder has woody cone-like structures that persist through winter.
Frequently asked questions
Is Populus trichocarpa native to California?
Yes. Populus trichocarpa is native to California (recorded as native).
When does Populus trichocarpa bloom?
Populus trichocarpa blooms Feb-Apr.
Where in California does Populus trichocarpa grow?
Populus trichocarpa occurs in Los Angeles, Ventura, San Bernardino, Santa Barbara, Kern, Riverside, El Dorado, Tulare and other counties, at elevations of 5-3050 m.
What plant family does Populus trichocarpa belong to?
Populus trichocarpa is in the Salicaceae family, genus Populus.
What habitat does Populus trichocarpa grow in?
Populus trichocarpa grows in Scattered. Alluvial bottomland, streamsides.
Related species
Other California species in the same genus, family, or bioregion.
- Populus alba — White poplar
- Populus angustifolia — Narrow-leaved cottonwood
- Populus fremontii subsp. fremontii — Alamo or fremont cottonwood
- Populus nigra — Black poplar
- Populus sp. — Cottonwood
- Populus tremuloides — Quaking aspen
- Salicaceae sp. — Willow family
- Salix alba — White willow
- Salix babylonica — Weeping willow
- Salix bebbiana — Bebb's willow
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-06
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.