Black Cottonwood

About Black Cottonwood in Alberta

Black cottonwood is a native Alberta poplar of western riparian landscapes, especially floodplains, river valleys, bars, and moist alluvial soils in the foothills and mountain-adjacent west. For Ancient Roots Alberta, it matters as a place-based native river tree: large old survivors on intact western floodplains can carry strong ecological and heritage value, especially where hybridization with balsam poplar complicates identity and remnant pure-looking trees become more significant.

Identification: Leaves are broad and relatively large, usually ovate to deltate or rhombic-ovate, about 7-12 cm long, with crenate or crenate-serrate margins. Upper surfaces are darker green and glossier, while lower surfaces are paler. The broad glossy leaf and pale underside combination is useful in Alberta, especially in riparian settings.

Alberta range and habitat: Black cottonwood is native in Alberta but is regionally restricted rather than broadly provincial. It should be treated as a western Alberta species, especially of foothill and mountain-adjacent river systems, not as a poplar occurring widely along major waterways across the whole province.