Populus balsamifera ssp. trichocarpa, the black cottonwood western balsam-poplar or California poplar, is a deciduous broadleaf tree species native to western North America. It is used for timber, and is notable as a model organism in plant biology. It is a large tree, growing to a height of 30 metres (98 ft) to 50 metres (160 ft) and a trunk diameter of over 2 metres (6.6 ft), which makes it the largest poplar species in the Americas. It is normally fairly short-lived, but some trees may live for up to 400 years. The leaves are 7-20 cm long with a glossy dark green upper side and glaucous light grey-green underside; larger leaves, up to 30 cm long, may be produced on stump sprouts and very vigorous young trees. The leaves are alternate, elliptic with a crenate margin and an acute tip, and reticulate venation (see leaf terminology). The petiole is reddish. The buds are conical, long, narrow and sticky, with a strong balsam scent in spring when they open. (Wikipedia) Photo credit: Amiyashrivastava CC BY-SA 3.0.