Plant Data Sheet: Antelope bitterbrush (Purshia tridentata)
Range
Bitterbrush
is found from
Climate, elevation
Bitterbrush
prefers a semi-arid, inland climate. It
is found from 60-3000 meters in elevation (2).
Local occurrence
Bitterbrush is common in the sagebrush steppe of eastern
Habitat preferences
Bitterbrush is typically found on open, well-drained flats, slopes, and valleys with deep gravel or rocky soils (2).
Plant strategy type/successional
stage
Antelope bitterbrush is shade intolerant. It is an early colonizer on disturbed sites, perhaps due to its nitrogen-fixing ability. In areas where bitterbrush dominates and natural regeneration is not occurring, old and large individuals may be the climax community. It is likely that overgrazing has changed the natural succession and role of bitterbrush in some communities (1).
Associated species
Bitterbrush
is often found in the following communities: Antelope bitterbrush-bluebunch
wheatgrass (Pseudoroegneria spicata),
antelope bitterbrush-Idaho fescue (Festuca
idahoensis), other steppe vegetation, and tree-dominated types such as
ponderosa pine (Pinus ponderosa)
forest and juniper (Juniperus spp.)
woodland (1,2).
May be collected as: (seed,
layered, divisions, etc.)
Bitterbrush
is typically collected as seed. Propagation by stem cuttings
is also possible, although specific details on the procedures are not readily
available (1).
Collection restrictions or
guidelines
Bitterbrush
reaches seed-bearing age in 8 to 10 years. Seeds ripen in late summer and generally turn from light in color,
to dark red, and then to gray as they ripen. The seeds can be collected by
shaking them from the bush onto a tarp or into a container. They should then be cleaned with a de-winger
and separated from the husks with a fanning mill (2).
Seed germination
The
bitterbrush seed is a leathery, oblong achene 0.6-1.25 cm in length. To break dormancy, it should be stratified for 2-7
weeks at 2-5°C. Stratified seed must be sown while wet. A five-hour soak in a three percent hydrogen
peroxide solution is an effective short-term treatment to improve germination (2).
Seed life and recommended storage
conditions
Field dried seed can be stored in bags in a cool, dry place for up to five years (2). Some studies have shown a germination rate of 74% after 25 years of storage when in proper conditions (1).
Propagation recommendations
Seed should be sown in the spring or fall. It should not be sown more than two centimeters deep (2).
Soil or medium requirements
The
propagation medium should be well drained.
Installation form (form, potential
for successful outcomes, cost)
Direct
seeding of antelope bitterbrush has shown mixed results. Research has shown
that direct seeding is fairly successful in pinyon-juniper communities, but less
so in big sagebrush and mountain brush types.
Establishing antelope bitterbrush from small seedlings requires good
seedbed preparation, including weed control.
Seedling survival can be very low, especially when the seedlings must
compete with cheatgrass (Bromus tectorum).
Installation of larger, containerize individuals has shown more success in some
studies (1).
Recommended planting density
Shrubs
should be installed 3-5 feet on center depending on the desired density and
expected mortality (3).
Care requirements after installed
Information
on care requirements was not available.
Supplemental water would, of course, increase survival of any plant in
an arid environment.
Normal rate of growth or spread;
lifespan
Adult
plants reach 0.5-2 meters in height. Bitterbrush is fairly slow
growing and long lived.
Sources cited
(1) Purshia tridentata. Fire effects
information website.
(2)
Rose, R. et al (1998). Propagation of
(3)
Sound Native Plants. http://www.soundnativeplants.com.
Retrieved
Data compiled by (student name and
date)
Sarah
Baker