Tacamahaca) are a group of about 10 species of poplars, indigenous to North America and eastern Asia, distinguished by the balsam scent of their buds, the whitish undersides of their leaves, and the leaf petiole being round (not flattened) in cross-section.

They are large deciduous trees, 30–60 m tall, with leaves with a rounded base, pointed apex, and a whitish waxy coating on the underside of the leaf; this latter distinguishes them from most other poplars.

Their leaves tremble in the slightest breeze like the quaking aspen[citation needed] The balsam poplar P. balsamifera (= P. tacamahaca, P. candicans) is a native of North America, where it grows on alluvial bottomlands in the northeastern United States and Canada.

[1][2] In the mountains of interior western North America, it is replaced by the willow-leaved poplar or narrowleaf cottonwood, P. angustifolia.

Simon's poplar (P. simonii), a native of northwestern China,[3] is frequently planted as a shade tree in northern European cities.

Another similar species is the laurel-leaf poplar (P. laurifolia from Mongolia[6]), which differs from its relatives in narrower leaves shaped like a bay laurel leaf.

The increased cellulose content would make them easier to convert into sugars and ethanol for biofuel or for pulp in paper mills.

The buds of various balsam poplars have long been combined with a lard base to make the vulnerary ointment Balm of Gilead.