Bitterbrush is native to western North America, where it is found
at elevations of 3281-8858' (1-2.7 km). It is found in sagebrush desert and ponderosa pine forests.
Its first known collection was by Meriwether Lewis
on the Lewis and Clark Expedition in July of 1806 near Lewis and Clark Pass, Montana. Frederick Pursh, the first to receive, work on, and publish the Lewis and Clark botanical collections, named the plant Tigarea tridentata in his 1814 publication, Flora Americae Septentrionalis.
Plants: Low, twisted, gnarly, and spreading, about 3' (91 cm) high and
6' (1.8 m) around. There are many horizontal, even prostrate branches and stems.
Leaves: Thick and small, less than 1" (2.5 cm) long,
with very fine hairs that make the plant look grayish. There are three separated teeth at the end of
each leaf, providing the “trident” in the species name “tridentata.” (There may be two more lobes
as well.) The leaves curl tightly during
droughts to reduce water loss.
Flowers: Creamy yellow or white, ¼-¾" (8-20 mm) aorund, with 5 petals and
an unruly collection of about 25 yellow-tipped stamens. Flowers appear from March to June.
Fruits: Slightly fuzzy, ⅛-¼" (5-7 mm) long, and tapered,
with achenes ¹/₃₂" (1.5 mm) long.