View photos of the medicinal plant Populus balsamifera (Balsam poplar), profiled in Medicinal Plants of the Western Mountain States.

A passage from Medicinal Plants of the Western Mountain States:

The therapeutic effects of Balsam poplar buds are essentially derived from two types of compounds. The first group, found in most other Willow family trees, is a combination of glycosides, mainly salicin and populin. These glycoside compounds (and derivatives) provide most of the buds (and bark) analgesic and antiinflammatory effects. The second group, which is more unique to resinous Populus species, is an array of balsamic and aromatic terpenes, not entirely dissimilar from conifer oleoresin. Here we have Poplar bud’s stimulating and antimicrobial influences. Due to these two groups of intermingled compounds and related therapeutic effects, Poplar bud’s application is somewhat broad.