Purshia tridentata is a slow-growing shrub up to 2 m in height and up to 2 m in width. The wedge shaped, three lobed leaves can vary in color from gray green to bright green. Flowers are small and vary from white to yellow in color. Seeds are relatively large, up to one-quarter inch long and obovate. This species blooms from late spring to early summer.
Purshia tridentata is distinguished by its 1 to 2 pistils, 5 to 7 mm long. Purshia stansburyana has 4 to 7 plumose styles, 20 to 60 mm long.
This is a starch rich species. Granules occur individually or in clusters of amyloplasts (sheets) bounded by cell walls. Granules observed from seeds are irregular in shape and can be up to 7 microns in length. They are oblong and angular. Granules generally have a centric to slightly eccentric hilum and curved cross arms. Quadrants are asymmetrical, typically with two larger and two smaller.
Purshia tridentata grows at elevations between 900 to 3400 m. It occurs naturally on dry lake beds, alluvial fans or terraces, and low foothills. P. tridentata grows in a mixed shrub community, but can also occur in pure stands. It is associated with a variety of understory grasses and forbs. It can also be an understory plant in association with taller growing trees.
This species grows across the western United States.
Western Native American groups used leaf poultice or wash for itches, rashes, insect bites, chickenpox, and measles. Leaf tea was used as a general tonic and for colds, pneumonia, liver disease, to expel worms, and as an emetic and laxative for stomach ache and constipation. Twigs, leaves, and berries were used as a laxative. Root teas were used for coughs, lung and bronchial infections, fever, and to facilitate delivery of placenta.
Northern Paiute: "[In regards to hunabi (antelope bitterbrush, Purshia tridentata) as it was used for medicine. There is a tall plant (4 or 5 ft high), a kind of bush growing in the mountains called hunabi. The leaves are picked and dried in the sun. They are boiled and drunk for stomach ache or for constipation. It makes them vomit and moves the bowels. It is gathered when the leaves are green at the end of June. It is also used for worms in the intestine. It is found near Hawthorne." (Fowler 1989:126)
Northern Paiute: "One cure for smallpox is prepared by boiling together the leaves of the Cowania, powdered rock lichens, and 'Kah-see' (dried urine of mountain rats). The solution is taken morning and night in doses of half-cupful...The same solution [a strong tea from boiled leaves and young stems, or sometimes the leaves and flowers] serves also as a physic...[and] for colds..." (Train et al. 1957:40)
Northern Paiute: "Judging from a number of reports this plant [Cercocarpus ledifolius] would appear to be one of th more important sources of medicinal remedies for the Indians...One Indian recommended that the bark be mixed with young twigs and leaves of Purshia tridentata and boiled, the cool decoction then being taken frequently for pains in the lungs due to tuberculosis." (Train et al. 1957:35-36)
Northern Paiute: "The boiled leaf decoction holds an important place among Indian remedies as a cure for venereal disease. The solution is taken as a tea...At Schurz the remedy for indicated specifically for gonorrhea. Some of the Indians prepare the liquid in quantity and store it in bottles. Some practitioners prefer a tea made from the inner bark of the trunks...Both Paiutes and Shoshones in many communities drink a tea made from the boiled leaves, or sometimes the twigs, when a physic or emetic is desired. Apparently the degree of action is regulated by the strength of the solution....Remedies from this plant are employed extensively in the treatment of smallpox, chicken pox, and measles...In the data secured from these different places there was no general agreement in the method or preparing the remedies nor in the mode of administration...As an internal medicant for the three diseases name above it was the usual custom to boil the leaves of the plant, although sometimes the leaves and younger branches were combined, and at times even the flowers were included. The quantity of the liquid to be imbibed at a time was not always indicated but apparently the amount should be less than a half-cupful due to the emetic properties of the decoction. In special reference to measles it was believed that the potion hastened the appearance of the rash...The external phases of these same diseases were treated in some communities also by employing the decoction as a wash...In fact the external wash was considered universally to be an efficacious antiseptic for any sort of itch, rash, skin eruption, scratch, or insect bite. The green leaves could be mashed and applied as a wet dressing for sores...or the dried leaves were dusted on as a powder....To prepare a tea for tuberculosis some of the Indians utilized the inner white bark from the base of the plant...but others used only the dried outer bark...The leaf decoction was reputed to be a good medicine for colds...for pneumonia...for liver trouble...and as a blood or general tonic." (Train et al. 1957:84-85)
Klamath: "Chäk'-lō.-A shrub commonly 1 to 1.5 meters (about 3 to 4 1/2 feet) in height, of a much darker green color than sagebrush (Artemisia tridentata), with 3 toothed leaves, and yellow five-petaled flowers nearly an inch diameter. It is a characteristic plant of the yellow pine forests and extends to somewhat lower altitudes in the upper parts of the sagebrush belt proper. From the fact that it is a reputed favorite food of the antelope, it often passes under the name 'buck brush.' The roots after steeping in water are drunk as a remedy for coughs and other lung and bronchial troubles. I was informed by an Indian that this is the best medicine they have for this class of complaints. They 'use it all the time.'...The dry ripe fruits, which are intensely bitter, mashed in cold water and drunk are sometimes used as an emetic. The purple stain derived from the outer seed coat is also sometimes used to produce a temporary color on arrows, bows, and other objects." (Coville 1897:98)