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Black Cottonwood, Downy Poplar, River Cottonwood, Swamp Cottonwood, Swamp Poplar

Populus heterophylla

Family: Salicaceae (sal-i-KAY-see-ee) (Info)
Genus: Populus (POP-yoo-lus) (Info)
Species: heterophylla (het-er-oh-FIL-uh) (Info)
Synonym:Populus argentea



Foliage Color:

Unknown - Tell us

Bloom Characteristics:

Unknown - Tell us

Water Requirements:

Requires consistently moist soil; do not let dry out between waterings

Where to Grow:

Unknown - Tell us


over 40 ft. (12 m)


30-40 ft. (9-12 m)

over 40 ft. (12 m)


USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

Sun Exposure:

Full Sun

Sun to Partial Shade


Unknown - Tell us

Bloom Color:


Bloom Time:

Late Winter/Early Spring

Mid Spring




Other details:

Unknown - Tell us

Soil pH requirements:

Unknown - Tell us

Patent Information:

Unknown - Tell us

Propagation Methods:

From softwood cuttings

From semi-hardwood cuttings

From seed; direct sow outdoors in fall

Seed Collecting:

Unknown - Tell us


This plant has been said to grow in the following regions:

Lisle, Illinois

Benton, Kentucky

Gardeners' Notes:


On Jul 24, 2016, Rickwebb from Downingtown, PA wrote:

This tree species is shown in the Golden Guide Field Guide of Trees of North America, but I have never seen any before until I saw some at Morton Arboretum that is west of Chicago, IL. It is native from MA to northern FL right along the East Coast, then also along the Gulf of Mexico from north FL to LA, then up the lower Mississippi to some of the Ohio River and the Wabash, then northwest IN, southern MI, and north Ohio. It is cold hardy to USDA Zone 5a. I am sure it is easy to grow like other poplars in draining wet to moist soils. I would guess the pH range would be 6.0 to 7.5 as most likely. Most of the soil at Morton Arboretum is from 6.5 to 7.0. I would use it as an interesting native shade tree for a naturalistic landscape or near a watercourse.


On Mar 30, 2005, melody from Benton, KY (Zone 7a) wrote:

I do not grow this plant...information only.

This tree is usually found in wet soils and has a narrow, rounded crown with stout branches.

Often found submerged in flood plains and edges of swamps. It's range is Connecticut south to GA and from N.W. Florida north to southern MI, below elevations of 800'. It is found in Eastern MO and AR.

It grows rapidly and is sometimes used as a shade tree.