Rio Grande Cottonwood

Rio Grande Cottonwood Tree

Rio Grande Cottonwood Tree

Scientific name: Populus wislizeni

Alternate names: Narrowleaf, Alamo or Guerigo

Description: This is the cottonwood of desert waterholes and watercourses. A deciduous poplar of the Willow family with broad, flattened, open crown of large, widely spreading branches & trunk diameter of 2 to 5 feet. Easily propagated from cuttings, it is extensively planted in its range along irrigation ditches. Although it is a fast-growing shade tree, it is short-lived.

Rio Grande Cottonwood Leaves

Rio Grande Cottonwood Leaves

Bark: The heartwood of this tree is deeper brown than that of Fremont cottonwood but the sapwood is white. On older trees, the bark is thick, deeply furrowed, reddish brown. On branches or on young trees, bark is thin, smooth and gray-brown.

Leaves: Roughly triangular in shape, 2 to 2.5 inches long and 2.5 to 3 inches wide. They are shiny green with a thin yellow midrib, a coarsely toothed margin & a yellow, flattened stem that causes the leaf to shake back & forth in the wind. Leaves turn bright yellow in autumn.

Rio Grande Cottonwood Fruit

Rio Grande Cottonwood Fruit

Twigs: light green, stout, hairless.

Flowers: Catkins 2 to 3 1/2 inches long, reddish; male and female on separate trees in early spring.

Fruits: Multiple 1/2 inch long, egg-shaped, seed bearing capsules in a clump, hairless, light brown, maturing in spring, splitting into 3 or sometimes 4 parts with many cottony seeds.

Habitat: Wet soils along streams or near lakes in deserts, grasslands & woodlands

Range: This tree occurs along the Rio Grande from Mexico to southern Colorado and in the San Juan basin in northwest New Mexico and southwest Colorado.

Rio Grande Cottonwood Bark

Rio Grande Cottonwood Bark

Height: 40 to 80 feet

Elevation: Up to 6500 feet

Water Requirements: Moderate-High. Rio Grande cottonwood grows only on wet soil and is an indicator of permanent water and shade. In the desert, it needs weekly watering during hot weather if roots cannot tap the water table.

Wildlife: Horses gnaw the sweetish bark; beavers feed on the bark and build dams with the branches.

2 comments “Rio Grande Cottonwood”

We have a young Rio Grande cottonwood tree (planted 3 1/2 yrs ago) that is about 30 ft. tall. It split about half way up the trunk and I don’t know if it can be saved or if it should be taken down. We live in the North Valley of ABQ and it has been healthy until now. Thank you for your reply.

Hi Sanja,

The best course of action is to have a certified arborist come out to look at the tree. Many of the local tree companies have certified arborists on staff. Certified arborists are trained in assessing situations such as the one you describe. Hoping for the best….


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