• IMPORTANCE TO LIVESTOCK AND WILDLIFE
• PALATABILITY
• NUTRITIONAL VALUE
• COVER VALUE
• VALUE FOR REHABILITATION OF DISTURBED SITES
• OTHER USES AND VALUES
• MANAGEMENT CONSIDERATIONS

IMPORTANCE TO LIVESTOCK AND WILDLIFE:

Reliance on the big sagebrush ecosystem by many wild animals for both food and cover has been documented and reviewed extensively [11,57,77,91,96,98,111,129,137]. Wildlife researchers have argued that the importance of sagebrush as forage, and effects of foraging on sagebrush are not fully appreciated [130,131,140]. Big sagebrush is eaten by domestic sheep and cattle, but has long been considered to be of low palatability to domestic livestock, a competitor with more desirable species, and a physical impediment to grazing [11,33,111].

PALATABILITY:

Wambolt [130,131] studied elk and mule deer preference for the 3 big sagebrush subspecies and black sagebrush. The study was conducted annually for 10 years on 2 sites in Yellowstone National Park. Each year approximately 2,500 leaders on 244 plants were examined for browsing. The percentage mountain big sagebrush leaders utilized during a given winter was as high as 91%. In all cases, mountain big sagebrush was used more than the other 3 taxa, with an average of 56.1% use. In 16 of the 20 samplings, use of mountain big sagebrush was significantly (P < 0.05) greater than that of Wyoming big sagebrush, the second most preferred taxon, which had an average of 38.6% use. Differences in preference among taxa were smallest during severest winters when more elk were present on the site.

Welch and Wagstaff [140] noted that mountain big sagebrush is a highly preferred and nutritious winter forage for mule deer. They argued that "The perception that big sagebrush is largely unsuitable and unused is due to low palatability to cattle and its ability to quickly mask evidence of use." The "Hobble Creek" low elevation, USDA cultivar [139] of mountain big sagebrush is preferred by both wintering domestic sheep and mule deer. The cultivar has not been found to contain substances that negatively influence preference or suppress grass cell wall digestion in ruminants [138,139,140].

NUTRITIONAL VALUE:

The Hobble Creek cultivar of mountain big sagebrush is a highly preferred sagebrush that exceeds most other winter forage values in energy, protein, phosphorus, and carotene. Winter crude protein content of the cultivar is 10%-11% of dry matter, winter in vitro digestibility is 52.6% of dry matter, winter phosphorus level is 0.21%, and total winter monoterpenoid content is 2.09%. A study comparing mule deer preference for the Hobble Creek cultivar against antelope bitterbrush indicated that mean usage did not differ after the first 2 measurements, but was significantly higher (P < 0.05) for the 2 final measurements. The sagebrush cultivar was significantly more digestible than antelope bitterbrush, and significantly higher in crude protein and phosphorus [138,139,140].

COVER VALUE:

The degree to which mountain big sagebrush provides cover for wildlife species has been reported as follows [32,33]:

	OR	UT	WY
pronghorn	-	fair	good
bighorn sheep	fair	-	-
elk	-	fair	fair
mule deer	good	fair	fair
white-tailed deer	-	-	poor
small mammals	-	good	good
nongame birds	-	good	good
upland game birds	-	good	good
water fowl	-	poor	good

VALUE FOR REHABILITATION OF DISTURBED SITES:

Mountain big sagebrush is easily propagated from seed under greenhouse, nursery, and common garden conditions [37,53,69,106,150,152] and has been successfully seeded directly into field sites [26,30,65,106,111,152].

The temperature for drying seeds for storage should not exceed 140 degrees Fahrenheit (60^oC). Humidity control is important for seed storage and should not exceed 32 to 40% [135,137]. Seed life in storage is about 5 years [111,137].

Mountain big sagebrush has also been successfully planted in field sites using nursery-grown bareroot and containerized stock [38,59,65]. After 3 years, percent survival of outplanted containerized seedlings in a Nevada study was as high as 80% in some plots [38]. Mountain big sagebrush has been propagated by tissue culture with limited success [95].

Please refer to the General Botanical Characteristics section of this report for more information about mountain big sagebrush regeneration.

Cotts and others [30] included mountain big sagebrush in a detailed study of revegetation methods for abandoned roads in Grand Teton National Park. They tested 14 treatments. After 2 growing seasons, treatments that included the addition of topsoil (collected locally), followed either by natural colonization of mountain big sagebrush, or seeded with locally collected seed from the same year, had much greater percent plant cover (P=0.05) than various other treatments. The most successful treatment, producing 7.3% cover, was a combination of vegetation removal, substrate scarification, topsoil application, and phosphorus application. Application of locally collected seed alone, following vegetation removal, produced a cover of 0.3%. Application of commercial seed alone following vegetation removal produced only a trace of mountain big sagebrush cover. Sites treated with a combination of locally collected seed with topsoil increased plant cover compared to various treatments without topsoil. More notably, mountain big sagebrush was the most dominant species to naturally colonize nonseeded, topsoiled treatments.

There is evidence that mountain big sagebrush is not aided by the addition of supplemental water and/or fertilizer under field conditions. In a Wyoming study where researchers applied water and ammonium nitrate to transplants on a reclaimed strip mine (regraded with original topsoil), for 3 successive years, there was no significant increase (P=0.05) in aboveground biomass [25].

OTHER USES AND VALUES:

Native peoples used big sagebrush leaves and branches for medicinal teas, and the leaves as a fumigant. Bark was woven into mats, bags and clothing [97].

MANAGEMENT CONSIDERATIONS:

The ecology of mountain big sagebrush in the West has been altered by post-settlement increases or decreases in historical fire intervals and livestock grazing, widespread invasion by exotic annuals, and perhaps climate change [11,23,83,143]. Historical abundance of big sagebrush has been disputed. According to reviews [7,143] and a comparative examination of 20 historical photos from 3 states [66], big sagebrush was abundant and codominant with perennial bunchgrasses in pre-settlement times. Sagebrush species do not appear to have increased their range on a large scale, but reviewers agree that big sagebrush has increased in density in many places in response to excessive grazing and altered fire regimes. Regarding the sagebrush steppe ecosystem, West [143] makes the following remark: "Some of it has been so degraded by excessive livestock grazing and burning that its relationship to its origins is no longer easily recognizable."

Important management considerations in sagebrush ecosystems include wildlife use, livestock grazing and overgrazing, fire frequency and hazard, exotic plant invasion and conversion of the ecosystem to other uses. Blaisdell and others [11] provide an extensive review and guidelines for integrating multiple uses of the sagebrush grasslands, including determining range condition and trend, and controlling sagebrush.

Perryman and Olson [99] argue that sagebrush control decisions are typically based on characteristics such as canopy cover, but should instead be based on ecologically based community-successional criteria. To aid managers they used annual growth rings to develop a quantitative model of age-stem diameter relationships for the 3 subspecies of big sagebrush. They sampled 75-80 stem cross-sections within 9 stands in regionally dispersed locations across Wyoming. Using the model, managers should be able to quickly assess the age (and perhaps successional status) of big sagebrush stands based on the stem diameter of large individuals. Stand age could then be compared with fire frequency information to determine if control practices should be implemented.

Because mountain big sagebrush often co-occurs with Wyoming big sagebrush and basin big sagebrush, please refer also to the Management Considerations section in FEIS reports for those subspecies.

Related categories for SPECIES: Artemisia tridentata spp. vaseyana | Mountain Big Sagebrush