Photo courtesy of Mary Ellen (Mel) Harte, bugwood.org
Purshia tridentata (Pursh) DC.
Scientific Name Synonyms:
Life Span: Perennial
Season: Evergreen and deciduous
Growth Characteristics: A many branched shrub with a rounded crown, usually growing 2 to 6 feet tall, but can grow up to 15 feet tall. It flowers April to July, fruits mature July to September. It reproduces from seeds.
Flowers/Inflorescence: Flowers are yellow, with 5 spatula-shaped petals, 5 sepals, and many stamens (20-25).
Fruits/Seeds:A spindle-shaped seedpod with a tapering hairy beak. Bitterbrush reaches seed-bearing age in 8 to 10 years.
Leaves: Evergreen and alternate. The leaf tip is 3-lobed, the margins entire and rolled under. The underside of the leaf is densely white-woolly. The leaves have a very bitter taste.
Stems: Twigs are gray to brown, with many short, spur-like branchlets, hairy at first and losing hair towards tip.
Bitterbrush occurs on foothills, mountain slopes, mesas, and open woodlands on all aspects, from 3,100 to 10,000 feet in elevation. It sometimes has nitrogen-fixing root nodules. It has excellent drought tolerance, is moderately browse tolerant, and is intolerant of shade. It is severely damaged by fire, especially if rain is not received shortly after the burn, or if the burn occurs in the spring when soils are moist.
Soils: Most abundant in well-drained sandy, gravelly, or rocky soils.
Associated Species: Snowberry, curlleaf mountain mahogany, basin wildrye, big sagebrush.
Uses and Management:
Bitterbrush is important browse for cattle, sheep, and goats, especially in late fall and winter when the ground is snow-covered. It is usually not eaten by horses. It is excellent browse for many species of wildlife, and can be critical winter browse for deer.