Overview
Populus fremontii is a large, fast-growing deciduous tree of the willow family, reaching 40-115 feet (12-35 m) tall with a broad, open crown and a thick, deeply furrowed grey trunk. The triangular leaves are 1.5-3 inches (4-7.5 cm) long with coarse, rounded teeth and flattened stalks that let them flutter in the wind. Plants are dioecious, with male and female catkins on separate trees opening in early spring before the leaves. Female trees release masses of small seeds wrapped in white cottony hairs that drift in early summer, the source of the name cottonwood. The roots run wide and shallow, seeking the water table along streams and floodplains. It grows in moist, well-drained alluvial soil in full sun and depends on a high water table, declining where rivers are dammed or pumped. Wood is soft and brittle, and large limbs can break in storms. It is a foundation species of southwestern riparian woodlands and a source of nesting sites and shade along desert watercourses.
Native Range
Native to the southwestern United States and northern Mexico, from California and Nevada east to Texas and south into Baja California and Sonora. It grows along rivers, streams, springs, and floodplains in arid and semi-arid country.Suggested Uses
Used as a fast shade tree for large, open, moist sites, in riparian restoration, and as a windbreak along watercourses, spaced 30-50 feet (9-15 m) apart. Male, cottonless selections are grown where seed fluff is a nuisance.How to Identify
Appearance
Size & Dimensions
Height40' - 115'
Width/Spread30' - 60'
Reaches mature size in approximately 25 years
Bloom Information
Catkins open in early spring, usually February to April, before the leaves emerge. Male and female catkins hang on separate trees and are wind-pollinated. Cottony seeds ripen and drift on the wind from late spring into early summer.
Detailed Descriptions
Foliage Description
greenGrowing Conditions
Sun Requirements
Requires 6-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Grows in full sun on deep, moist, well-drained alluvial soil at a pH of 6.0-8.0 and needs a reliable water table or regular deep watering. It is fast-growing, often adding 6 feet (1.8 m) or more a year when young, and roots aggressively toward water. The soft, brittle wood drops limbs, and shallow roots can lift paving and invade drains, so it is grown in open spaces well clear of buildings. Hardy in zones 7-10, it tolerates heat and seasonal flooding but not prolonged drought once the water table drops. It is grown easily from dormant cuttings or seed. Female trees shed cotton, so male selections are planted in tidy landscapes.Pruning
Prune in late summer or fall to avoid heavy spring sap bleeding, removing dead, broken, or crossing limbs. Formative pruning when young builds a stronger framework in this brittle-wooded tree. Large pruning wounds heal slowly and can invite decay.Pruning Schedule
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