• 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:

Spiny hopsage is tolerant of grazing and where abundant is a valuable browse plant for many species of wildlife and livestock [6,9,45,67]. Spiny hopsage provides a palatable and nutritious food source for big game and livestock, particularly during late winter through spring [54]. Its relative forage value may be less during the fall when it has been described as "useless." However, Stubbendieck and others [66] describe spiny hopsage as being browsed by livestock in the fall, winter, and spring. Spiny hopsage is used as forage to at least some extent by domestic sheep and goats, deer, pronghorn, and rabbits [73].

On bighorn sheep ranges in east-central Idaho, Lauer and Peek [32] reported heavy use of spiny hopsage. It receives at least some winter pronghorn use in Utah [61]. Spiny hopsage provides food for the mountain cottontail in south-central Idaho [29]. In northeastern California, spiny hopsage is a major food of the black-tailed jackrabbit [12]. Spiny hopsage seedlings are eaten by a variety of small mammals including Botta's pocket gopher, Merriam's kangaroo rat, southern grasshopper mouse, deer mouse, and desert cottontail [54].

Spiny hopsage provides browse for domestic sheep in parts of Wyoming [36] and is described as a “good” forage species for domestic sheep in Utah. Domestic sheep browse the succulent new growth in late winter and early spring [25,26]. In north-central Wyoming, spiny hopsage occurs with greasewood and winterfat and provides forage for winter livestock [16]. In Utah, spiny hopsage is important in the diet of domestic sheep only during early spring [19]. In the Mojave Desert, domestic sheep browse spiny hopsage late in the growing season [43]. The large quantities of seeds produced are valuable for fattening domestic sheep [66]. Minor damage to livestock may result from the spines [6,67].

Van Dyke and others [72] reported moderate fall use of spiny hopsage by bighorn sheep in southeastern Oregon.  

PALATABILITY:

Spiny hopsage is considered one of the most palatable of the salt desert shrubs, particularly during the spring. However, overall value is limited in most areas since leaves and fruits are shed by early summer [54]. Early spring growth is very palatable, but by mid-summer palatability is very poor.

Spiny hopsage retains very little edible forage over the fall and winter [45]. However, Wasser [73] reports fair to good palatability for deer and domestic sheep and goats in the late fall, winter, and spring. Palatability to cattle is described as “fair to poor” and palatability to horses is rated as “poor to useless” [7]. The degree of preference shown by browsing animals apparently varies greatly according to ecotypic variability by stand [81]. Thorns may keep spiny hopsage from being utilized [6,67].

The degree of use shown by livestock and wildlife species for spiny hopsage in several western states is rated as follows [10]:

                       CO          OR        UT          WY         
  
Cattle                 Fair        ____       Fair       Fair         
Domestic sheep         Good        ____       Good       Good
Horses                 Fair        ____       Good       Good    
Pronghorn              ____        ____       Fair       Fair 
Bighorn                ____        Fair       ____       ____       
Elk                    ____        ____       Fair       ____  
Mule deer              ____        ____       Fair       Poor
White-tailed deer      Poor        ____       ____       ____
Small mammals          Fair        ____       Good       Good
Small nongame birds    ____        ____       Poor       ____ 
Upland game birds      ____        ____       Fair       ____ 
Waterfowl              ____        ____       Poor       ____

NUTRITIONAL VALUE:

Spiny hopsage is rated "fair" in energy and protein value [10]. In southwestern Idaho, crude protein of foliage averages 18% during late winter and 11.8% in the summer months [54]. Nutritional content of spiny hopsage, expressed as a percentage of dry matter, is as follows [41]:

                                Aerial Part,  Aerial Part,   Pods,   
                                Fresh         Leaves, Fresh  Dormant                       
Ash (%)                          5.1          30.0           23.0      
Crude Fiber (%)                 38.3           9.2           22.2
Ether Extract (%)                2.0           1.7            1.2      
N-Free Extract (%)              45.7          48.3           44.8 
Protein (N × 6.25) (%)           8.9          10.2            8.8 
 cattle: digestible protein (%)  5.5           6.2            5.0 
 cheep: digestible protein (%)   5.3           6.5            5.2
Phosphorus %                     0.19          ---            --- 

      N(%)      P(%)      Na(%)     K(%)     Ca(%)     Mg(%)    
leaf  2.23      0.09      0.175     10.13     4.25      2.15      
stem  ----      0.08      0.009      6.06     1.23      0.51   

      Si(mg/g)  Zn(mg/g)  Cu(mg/g)  Fe(mg/g) 
leaf  0.07      37        5         150   
stem  0.01      16        3          20

COVER VALUE:

Spiny hopsage provides good cover for birds, rodents, and lagomorphs, even when dormant [37,54]. Waterfowl, including mallards, use it for nesting cover in eastern Washington [21].

The degree to which spiny hopsage provides environmental protection for wildlife species in two western states is as follows [10]:
                              UT           WY

      Pronghorn               Poor         Fair 
      Bighorn                 ____         ____
      Elk                     Poor         Poor
      Mountain goat           ____         ____
      Mule deer               Poor         Poor
      White-tailed deer       ____         Poor
      Small mammals           Fair         ____
      Small nongame birds     Fair         ____
      Upland game birds       Fair         Fair
      Waterfowl               Poor         ____

VALUE FOR REHABILITATION OF DISTURBED SITES:

Spiny hopsage has moderate potential for erosion control and low to high potential for long-term revegetation projects [10]. It can improve forage, control wind erosion, and increase soil stability on gentle to moderate slopes [27,54]. Spiny hopsage is suitable for highway plantings on dry sites in Nevada [64]. Generalized characteristics for use in rehabilitation are as follows [44]:

        Adaptation attribute            Rating

        establishment by seed           medium  
        establishment by transplant     medium
        seed production & handling      medium  
        natural spread by seed          medium  
        growth rate                     good
        soil stability                  medium
        natural vegetative spread       very poor
        adaptability to disturbance     medium

             # of individuals    # of individuals    survival    
              transplanted          surviving          (%)          
                   25                  10               40             

First-year survival of front-end loader transplants (soil pH 7.0-8.0):
				  
             
             # of individuals    # of individuals    survival
              transplanted          surviving          (%) 
                   90                  64               71  
       
 

Spiny hopsage can be seeded directly onto disturbed sites in northern shrub steppe communities [54]. Best results are generally obtained when seeds are planted in late fall or early winter which provides stratification [57,54]. Seed remains viable up to 2 years in storage. Plummer [44] recommends selecting seed by matching an ecotype that grows under conditions similar to those where it is to be planted. According to Plummer [44], "plant characteristics such as growth form, rooting depth, palatability, ease of establishment, and resistance to grazing should be used." Spiny hopsage seed is commonly cleaned by hammermilling to remove appendages from the utricles and then fanned to remove debris [59]. Seedling establishment for broadcast and planted seeds was as follows [79]:

Seedbed                      Seeds with             Seeds with                                
characteristics              entire bracts          bracts removed
                                (%)                     (%)                    
loose surface                    18                       2
smooth surface                    7                       0
packed surface                    4                       0
seeds planted 0.5 cm deep        51                      48
 

OTHER USES AND VALUES:

Some Native American peoples traditionally ground parched seeds of spiny hopsage to make pinole flour [66].

MANAGEMENT CONSIDERATIONS:

Spiny hopsage readily establishes and increases on overgrazed and denuded ranges [62]. Plummer and others [45] report that in Utah, spiny hopsage has a poor natural rate of spread.

             composition (%)     cover (shrubs/m2)
grazed       17                  0.378
ungrazed     19*                 0.533*
_____________________________________________________
*significant difference between treatments (p<0.05)

Spiny hopsage accumulates potassium in its leaves to such an extent that decay of the leaf litter may raise the surface soil pH beneath the canopy. These soil changes may affect future growth of spiny hopsage and other shrubs growing in association [50]. However, according to Rickard and Keough [50], "whether these mineral concentrations will tend to make the soil more or less suitable for future generations of shrubs remains to be seen."

Related categories for SPECIES: Grayia spinosa | Spiny Hopsage