Description: Tree with broad, flattened, open crown of large, widely spreading branches.

Height: 12-25 m.

Diameter: 0.6-1.2 m

Leaves: 5-7.5 cm long and wide. Broadly triangular, often broader than long, short-pointed, nearly straight at base; with coarse, irregular, curved teeth; thick, hairless; petioles long, flattened. Shiny yellow-green; turning bright yellow in autumn.

Bark: Grey, thick, rough, deeply furrowed.

Shoots: Light green, stout, hairless.

Flowers: Catkins 5-9 cm long; in early spring; reddish; diecious. Female flowers of Populus fremontii have short (2-3 mm) stalks, whilst those of closely similar Rio Grande Cottonwood (var. wislizeni) are longer, c 12mm.

Fruit: c 12mm long, egg-shaped capsules, light brown, hairless; maturing in spring, splitting into three parts with many cottony seeds.

Habitat: Wet soils along streams, often with the western Platanus species, willows and alders; in deserts, grasslands and woodlands.

Range: S and W Colorado west to N California and southeast to Trans-Pecos Texas; also N Mexico; to 2000m. Rio Grande Cottonwood (treated as a separate species, Populus wislizeni Sargent by some authors) replaces Frémont Cottonwood to the south and east, in Texas and New Mexico. The range map includes both.

This species, including varieties, is the common cottonwood at low altitudes along the Rio Grande and Colorado River and in the rest of the southwest, as well as California. Frémont Cottonwood grows only on wet soil and is an indicator of permanent water and shade. Easily propagated from cuttings, it is extensively planted in its range along irrigation ditches, and although it grows rapidly, it is shortlived. Hopi of the Southwest carve cottonwood roots into kachina dolls, the representations of supernatural beings. Horses gnaw the sweetish bark (unlike its relative, Narrowleaf Cottonwood); beavers also feed on the bark and build dams with the branches. The tree is named after its discoverer General John Charles Frémont (1813-90), soldier, explorer and politician. It does not seem to have been introduced to the UK before 1904. A large tree at Thorp Perrow was referred to this species, although it seemed rather different in leaf form and we were watching it carefully. However, Thorp Perrow seem to have taken the view that this tree was getting too old for public safety and have felled it, along with many others in that area. We don't know of any other specimens in the UK.

Information: Audubon (1980) , Bean III (1976).

Source: Seed collected by Jake Turin, from bosque of Rio Tesuque, Cuyamungue, Santa Fe County, New Mexico, in June/July 1994. We believe that this provenance means that the trees are var. wislizeni.

Received: 1994.07.18, by airmail.

Sown: Two pots of nine each in different composts, on morning of receipt. Seeds kept refrigerated and sown a few days later had lost viability.

Progress: First germination in 48 hours, total of eight seedlings after 96 hours. Six of these survived to be potted, and only one was lost in the following four years. All grow well if given enough root space and nutrients, though they stay fairly small if kept in smaller pots. The first was planted out at the southern end of our US strip, at B0A, in damp soil just inside the boundary wall (with a small stream on the far side) on 1995.06.05 at about 0.9m. This unfortunately proved to be just in reach for marauding cows who chewed the top off twice in succeeding years. Despite this, the tree was 2.25 m on 1998.10.07. Although nominally a fast growing tree, SW County Durham is quite a bit cooler than New Mexico in the summer and this tree was not adding much girth year by year. One of our potted specimens reached 1.6m on the same date, and was planted at B32H on the west side of the American tree strip 1999.05.11, but does not seem to be happy with the site. Overall, the Rio Grande variety (or species) does not seem to thrive here and all the trees died early in the 21st century. One of the potted ones was given away to a friend with a more sheltered lowland site, but we're not sure how that's getting on.

Anyone out there is the western USA care to send us some seed for a hardier provenance of the type species ? Or anyone planning a tourist trip in the autumn like to bring us back some cuttings ? Email user <trees> at our site <pennine.demon.co.uk>. We really would like some of these trees.

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