Bitterbrush is a long-lived, native shrub that has a number of common names including quinine brush, black brush, antelope bitterbrush, deerbrush and buckbrush. It is an important browse plant. Its palatability is good and the nutrition remains high year round.

Description

The growth form of bitterbrush is variable, ranging from sprawling, semi-erect to erect and varying from 3 to 6 feet in height.

Bitterbrush is semi-evergreen with small, three-toothed leaves. A new crop of leaves develops in the spring and another in the fall. Those that develop in the fall are persistent throughout winter even though the plant is dormant in the winter.

Bitterbrush has butter-yellow, small, rose-like blossoms in late June or early July and bears abundant seed that is easily harvested. The seed ripens quickly, four to seven days after bloom, and falls within a week after ripening.

The bitterbrush plant, with its attractive fragrant yellow flowers, is suitable for beautification purposes.

Adaptation

Bitterbrush grows on well-drained, dry, sunny sites up to 8,500 feet in elevation. Flooding is poorly tolerated, and drought tolerance and winter-hardiness are good.

Bitterbrush prefers deep soils of sand or sandy texture (though it may range through the textures to clay) on low fertility sites of slightly basic to slightly acid pH. Moderate salinity is slightly tolerated.

Establishment

Quality, commercial bitterbrush seed generally possesses a purity of approximately 95 percent and a germination of about 85 percent. The seed germinates rapidly and is enhanced by pre-chill, but does not require it. Treatment of the seed with a three percent thiourea solution maximizes germination potential. Seedlings are fairly vigorous and survival is good. Resistance to insects and disease is high and partial shading is not detri-mental. Fall or early spring planting is recommended to take advantage of the improved germination response with stratification.

Management and Care

Bitterbrush seedlings need as much protection as possible from livestock, deer and jackrabbits, until the plants reach 8 to 10 inches in height (usual-ly three or four years).

Bitterbrush persists under heavy use, but loses vigor and productive capacity. Allowable grazing use should be no greater than 50 to 60 percent of the annual twigs. Bitterbrush is considered to be a indicator of good condition range.

Protect from fire as the plant is very flammable and regrowth is very slow.

Uses

The leaves and twigs of bitterbrush are important browse for livestock and big game animals. To sheep, bitterbrush is a choice food. For cattle, it is a fair food, eaten mostly when green grasses are not available. Horses seldom eat bitterbrush. Cattle and sheep graze bitterbrush in late summer, fall and winter. Wherever it occurs, bitterbrush is generally one of the key species on big game ranges. Relative palatability varies from fair to excellent. In pure stands it is often lightly used; but when it occurs as scattered plants with other shrubs, it is heavily used.

The leaves and twigs are choice food for muledeer, and fair food for antelope and elk. The use is primarily in winter, but also substantial in late summer and fall. Jackrabbits feed heavily on bitterbrush, especially on young plants.

The seeds of bitterbrush have little value to birds, as rodents eat most of the supply. The seed is an important food for mice and other rodents. Seedlings are eaten by mice, squirrels, chipmunks and jackrabbits.

Nutrient content is high. Protein content averages 12 percent in the spring, and declines to about eight percent in the winter. The nutritional value of bitterbrush is generally satisfactory for wintering livestock and big game.

Bitterbrush is potentially useful as a soil stabilizer or barrier planting on coarse, fine-textured soils subject to severe drought and where high-quality browse is required for livestock or wildlife use from fall through early spring.

Seed Production

Seed from bitterbrush ripens quickly, four to seven days after bloom, and falls within a week after ripening.

Seeds can be collected when they are in "heavy-blood stage." Usually a canvas collector is placed under shrubs and the seed is then beaten off.