Populus fremontii, commonly known as Frémont's cottonwood,[1] is a cottonwood (and thus a poplar) native to riparian zones of the Southwestern United States and northern through central Mexico.[2] It is one of three species in Populus sect. Aigeiros. The tree was named after 19th-century American explorer and pathfinder John C. Frémont.
A riparian tree, it grows near streams, rivers, springs, seeps, wetlands, and well-watered alluvial bottomlands at elevations below 2,000 metres (6,600 ft) elevation.[2][5]
P. fremontii is a large tree growing from 12–35 m (39–115 ft) in height with a wide crown, with a trunk up to 1.5 m (4 ft 11 in) in diameter. The bark is smooth when young, becoming deeply fissured with whitish, cracked bark on old trees.
The 3–7 cm (1.2–2.8 in) long leaves, are cordate (heart-shaped) with an elongated tip, with white veins and coarse crenate teeth along the sides, glabrous to hairy, and often stained with milky resin.[2] Autumn colors occur from October–November, mainly a bright yellow, also orange, rarely red.[2][6]
The inflorescence consists of a long, drooping catkin, which blooms from March to April. The fruit is a wind-dispersedachene, that appears to look like patches of cotton hanging from limbs, thus the name cottonwood.
The largest known P. fremontii tree in the United States grows in Skull Valley, Arizona. In 2012, it had a measured circumference of 557 in (14,100 mm), height of 102 ft (31 m), and a spread of 149.5 ft (45.6 m).[7]
Two subspecies are currently recognized. Some confusion due to hybridization with a Rio Grande subspecies of Populus deltoides subsp. wislizeni had originally placed this eastern cottonwood subspecies as a P. fremontii subspecies, but it was removed in 1977.[8]
P. f. subsp. fremontii, with synonyms P. f. var. arizonica - Sarg. and P. f. var. macdougalii - (Rose) Jeps. from California and west of the Continental Divide[8]
P. f. subsp. mesetae - Eckenwal., of arid areas of Mexico and west Texas, and widely planted elsewhere, generally east of the Continental Divide[8]
Native Americans in the Western United States and Mexico used parts of Frémont's cottonwood variously for a medicine, in basket weaving, for tool making, and for musical instruments. The inner bark of Frémont's cottonwood contains vitamin C and was chewed as an antiscorbutic - treatment for vitamin C deficiency. The bark and leaves could be used to make poultices to reduce inflammation or to treat wounds.
^Van Buren, Renée; Cooper, Janet G.; Shultz, Leila M.; Harper, Kimball T. (2011). Woody Plants of Utah: A Field Guide with Identification Keys to Native and Naturalized Trees, Shrubs, Cacti, and Vines. Logan, Utah, United States: Utah State University Press. p. 412. ISBN978-0-87421-824-4.
