• 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:

Wyoming big sagebrush is preferred browse for wild ungulates [22,105,116,141], and Wyoming big sagebrush communities are important winter ranges for big game [67,90,99,131]. Pronghorn usually browse Wyoming big sagebrush heavily [2]. On the Idaho National Engineering Laboratory, for example, the shrub comprised 90% of the diet of pronghorn from fall through spring. Lagomorphs may browse Wyoming big sagebrush heavily in winter [58]. Wyoming big sagebrush is a crucial food item of sage grouse, and Wyoming big sagebrush communities are critical habitat for the birds [4,31,52,53,131,143].

Livestock browse Wyoming big sagebrush, but may use it only lightly when palatable herbaceous species are available [102,117]. In south-central Wyoming, Wyoming big sagebrush formed about 10% of the spring and summer diet of domestic sheep. Cattle use was negligible. In contrast, it formed 85% of the spring diet of pronghorn on the same range [102]. In a Gambel oak (Quercus gambelii) community in northern Utah, domestic goats preferred almost any other browse to Wyoming big sagebrush [108].

PALATABILITY:

Wyoming big sagebrush is generally the most palatable of the big sagebrush subspecies, and big game species use it heavily, especially in winter [112,131]. In a trial using captive mule deer, it was the most preferred among the 3 major subspecies of big sagebrush [22]. It is moderately palatable to cattle and domestic sheep [131].

Coumarin, a compound present in big sagebrush leaves, imparts a bitter taste that affects animal use. There are regional differences in ungulate use of Wyoming big sagebrush relative to other big sagebrush subspecies, which may be at least partially due to between-population differences in coumarin concentration in Wyoming big sagebrush leaves [136,141]. For example, domestic sheep on the Kaibab Plateau of Arizona preferred Wyoming big sagebrush over either mountain or basin big sagebrush. Mule deer selected Wyoming big sagebrush as their 2nd choice among the 3 subspecies, but preferred mountain big sagebrush [142]. In eastern Oregon, however, Wyoming big sagebrush was the least palatable of 7 sagebrush taxa to domestic sheep but was moderately palatable to mule deer [117].

NUTRITIONAL VALUE:

Wyoming big sagebrush contains volatile oils, but is otherwise a highly nutritious shrub. The leaves equal alfalfa (Medicago sativa) in protein content, with slightly more carbohydrates and 12 times more lipids. Mule deer apparently avoid some of the effects of the volatile compounds by belching the compounds as they chew their cuds [98].

Nutritional content (%) of fresh big sagebrush browse is as follows [100]:                                        

Ash              3.1                 Protein (N x 6.25)     
Crude fiber  13.2                   cattle                 3.3
Carotene (mg/kg) 10.             domestic goats  3.0
Ca                0.37                   horses               3.1
Mg              0.11                    rabbits              3.2
P                 0.09                    domestic sheep 3.2
                             

COVER VALUE:

Wyoming big sagebrush provides cover for a variety of wildlife including pronghorn [126,130], bighorn sheep [83], lagomorphs [80,140], shrub-nesting birds, and some ground-nesting birds including sage grouse [71,80]. Cover of mature shrubs is especially important to pronghorn fawns and sage grouse brood [80,130]. Early to mid-seral communities are important black-tailed jackrabbit and pygmy rabbit habitats [80,88,140]. In contrast, Townsend's ground squirrels, and raptors that rely on them as prey species, prefer open and grassy, early seral Wyoming big sagebrush communities such as burns. Their numbers decline as plant succession advances [80].

VALUE FOR REHABILITATION OF DISTURBED SITES:

Wyoming big sagebrush is used for stabilizing slopes and gullies and for restoring degraded wildlife habitat, rangelands, mine spoils, and other disturbed sites [90,116]. It is particularly recommended on dry upland sites where other shrubs are difficult to establish [94]. It can be established by direct seeding [94,116] and by transplanting greenhouse seedlings or wildings. Wild plants are best moved while dormant in winter [90,119]. Commercial seed is available [35].

Wyoming big sagebrush has been recommended for seeding on coal-mined lands based upon tolerance of germinants to droughty and saline soils [41].

OTHER USES AND VALUES:

Native Americans made tea from big sagebrush leaves. They used the tea as a tonic, an antiseptic, for treating colds, diarrhea, and sore eyes, and as a rinse to ward off ticks. Big sagebrush seeds were eaten raw or made into meal [98]. The wood is extremely aromatic when burned, and the wood smoke was used to mask the effects of an encounter with a skunk [45].

Big sagebrush was little used by European-American settlers. They occasionally used the branches for thatching [135]. The wood produces a very hot fire, and was used in mine smelters [98].

Big sagebrush has little current commercial use. It is sometimes used for xeriscaping [64,98].

MANAGEMENT CONSIDERATIONS:

Grazing: Wyoming big sagebrush normally appears in mid-seral steppes, and good grazing management will not prevent its reinvasion [62]. It may increase moderately under heavy grazing; however, because of its relatively high palatability it does not increase as much as other big sagebrush subspecies usually do [112,131]. Schlatterer [113] reported that in northern Idaho, Wyoming big sagebrush increased slightly with overgrazing. On some overgrazed sites, Wyoming big sagebrush has declined nearly as much as associated bunchgrasses, and its coverage has actually increased with cessation of grazing. On the Upper Snake River Plains of southeastern Idaho, Wyoming big sagebrush and associated bunchgrasses were depressed from approximately 50 years of heavy domestic sheep and cattle grazing. When grazing was stopped in 1950, Wyoming big sagebrush cover increased significantly (p=0.05), from 15% in 1950 to 22% by 1965 [3].

Total productivity in Wyoming big sagebrush communities is low, from less than 400 lbs/acre (450 kg/ha) on poor sites to 900 lbs/acre (1013 kg/ha) on the most productive sites [112].

Control: Wyoming big sagebrush can be controlled by burning or with herbicides. Because Wyoming big sagebrush provides palatable browse for livestock and big game animals, even on poor soils, Beetle and Johnson [11] recommend caution when reducing it. Among control methods, fire is the most effective [8,32,137,138] (see Fire Effects). It is also the least expensive [138]. Bastian and others [8] present an economic threshold analysis integrating cost-effectiveness of fire or 2,4-D control on Wyoming big sagebrush rangelands, projected over 15 to 25 years, with breakeven return per AUM. Their model predicts that chemical control is generally about twice as costly as fire control.

Phenoxy herbicides generally control Wyoming big sagebrush [4,32,79,85,137]. In central Nevada, 2,4-D caused a 75% reduction in Wyoming big sagebrush [32]. Winter or early spring spraying reduces Wyoming big sagebrush at a time when most herbaceous species are dormant and less harmed by herbicides [4].

2,4-D does not effectively control Wyoming big sagebrush in New Mexico (35-50% mortality) [6,91]. Teuthiuron application resulted in 80% mortality of Wyoming big sagebrush in northern New Mexico [6].

Related categories for SPECIES: Artemisia tridentata ssp. wyomingensis | Wyoming Big Sagebrush