• 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:

Desert wheatgrass and its close relative, crested wheatgrass, have been planted in millions of acres in the arid and semi-arid West to benefit livestock and wildlife. Native shrub habitats have been replanted with desert wheatgrass to increase range production. Desert wheatgrass has high yields and supplies green forage in both spring and fall making it an important early season food source [52]. Desert wheatgrass is resilient under grazing pressure [60].

PALATABILITY:

Desert wheatgrass is highly palatable to livestock and wildlife, but it tends to become fibrous at maturity. Palatability and nutritional quality of the plant decline after June or so [34]. A frequently mentioned characteristic of desert wheatgrass is its tendency to form “wolf” or “stag” plants when ungrazed, which are plants thick with standing dead material. Wolf plants are unpalatable to livestock and decrease the forage potential of the stand [81].

Elk eat desert crested wheatgrass readily when its available [55,90].

Wildlife and livestock use of desert wheatgrass is outlined in the following table [15,36,58,67,83,76]:

              AZ         CA         MT         NV        OR
Cattle        ----       ----       high       ----      high
Elk           medium     ----       ----       ----      ----
Mule deer     medium     low        medium     low       ----
Pronghorn     ----       ----       low        low       ----

NUTRITIONAL VALUE:

Desert wheatgrass provides highly nutritional forage for livestock, especially in the early spring. As the growing season progresses, the nutritional value—in terms of phosphorous, nitrogen, crude protein, and digestibility—and palatability of desert wheatgrass decrease [3,48,65], and may drop below the nutritional requirements of cattle [36] and domestic sheep [69]. In Utah, winter crude protein values of desert wheatgrass were marginally deficient for grazing sheep [34].

Mule deer do not prefer desert wheatgrass to native shrub and grass species, but in captive deer feeding trials in the Great Basin, desert wheatgrass proved nutritious to mule deer. In vivo digestibility of a pure desert wheatgrass diet averaged 62% over a 20-day feeding trial in April. This figure is much higher than what is expected for available late winter and spring forages. Crude protein levels for fall, winter, green-up, and spring, were 23, 15, 23, and 30%, respectively. These levels are all good to excellent for the needs of mule deer, although deer may not be able to take advantage of the plant due to snow cover [90,91]. These levels are also higher than those cited by most authors [64].

In tractable elk feeding trials in the Great Basin, digestibility averaged 74% for the late vegetative stage and 53% for the late bloom stage [90].

Heinrichs and Carson [44] established the following nutritional values for desert wheatgrass in a trial in Saskatchewan, Canada:

            Protein     Nitrogen-free   Ether       
            content(%)  extract(%)      extract(%) 
			
early leaf  20.4        43.8            2.04       
short blade 14.8        49.0            1.62           
flower       6.6        54.6            1.19      
mature seed  6.0        55.5            1.55      
late fall    3.8        48.7            1.35      
next spring  3.3        47.4            0.79      

             Crude       Lignin          Ash       Ca       P
             fiber(%)    (%)             (%)       (%)     (%)
early leaf   25.0.       6.0             8.8       0.21    0.21
short blade  26.9        ----            7.6       0.24    0.17
flower       32.3        11.4            5.3       0.19    0.11
mature seed  31.4        11.9            5.6       0.25    0.09
late fall    40.4        15.7            5.8       0.23    0.03
next spring  42.9        ----            5.6       0.22    0.0
            			

Mineral     Requirement     Date
N           1.47%           June 8
P           0.28%           April 12
S           0.10%           July 4
K           0.60%           October 5
Zn          20 ppm          March 30
Ca:P        > 7:1           Never
N:S         > 15:1          June 2
N:S         < 10:1          July 19

COVER VALUE:

Desert wheatgrass and hybrids of desert and crested wheatgrass provide preferred cover and food for black-tailed jackrabbits in Nevada, Idaho, and Utah [29,35,47], and for mountain cottontails on the upper Snake River Plain in Idaho [54].

Seeding of historically sagebrush-dominated communities to desert wheatgrass may replace the shrub habitat necessary for many passerine birds [66,95].

Deer mice occupy moderately grazed desert wheatgrass range in Utah. Food in their caches on these sites was predominantly mature desert and crested wheatgrass seedheads. When grazing exceeded 50% use, the deer mouse population dropped by at least 20% [32].

VALUE FOR REHABILITATION OF DISTURBED SITES:

Desert wheatgrass has been used extensively to seed unused crop land and to revegetate burns, mines, road cuts and degraded areas [2,14,82,84]. Land managers have had some success preventing the spread of exotic weeds like halogeton (Halogeton glomeratus) and leafy spurge (Euphorbia esula) by seeding unused land with desert wheatgrass [73]. However, heavy grazing appears to neutralize this benefit [33].

Desert wheatgrass roots may extend past 6.6 feet (2 m) into the soil, contributing to desert wheatgrass’ ability to stabilize soils and reduce erosion [39].

OTHER USES AND VALUES:

No entry

MANAGEMENT CONSIDERATIONS:

Desert wheatgrass is a major host for black grass bugs (Labops hesperius) which can result in extensive defoliation. Burning and grazing appear to reduce the infestations [43].

Related categories for SPECIES: Agropyron desertorum | Desert Wheatgrass