and averaged 1,219 lb/acre (1 369 kg/ha). The bulk of this 

 was divided rather evenly between grasses (50 percent) 

 and forbs (46 percent); only 4 percent was shrubs. Of the 

 undergrowth, 35 percent was classified as desirable and 

 60 percent was of intermediate forage suitability. The 

 type, therefore, is moderately productive livestock range, 

 particularly for cattle. Because this type apparently has 

 been altered considerably by heavy grazing, its potential 

 for producing forage is probably greater than its current 

 production. Judging from perceived successional relation- 

 ships, the proportion of palatable forbs and possibly 

 shrubs was at one time much greater than at present. 

 Wildlife habitat values are comparatively low because of 

 the simplicity of vegetation structure and lack of under- 

 growth diversity. 



This serai type has not been reported elsewhere. But 

 because it is believed to represent a grazing-degraded 

 stage of the POTR/SESE c.t. and possibly the 

 POTR/SYOR/SESE type, which are both present in sur- 

 rounding States, this serai type likely occurs there as 

 well. 



Figure 11.— The Populus 

 tremuloides/Bromus 

 carinatus c.t. is probably a 

 grazing-induced serai type 

 created by heavy, prolonged 

 sheep grazing of a climax 

 POTR/SESE c.t. The 

 undergrowth in this stand in 

 the upper part of the 

 Seventeen Mile Creek drain- 

 age of the Fishlake National 

 Forest is dominated by B. 

 carinatus and Agropyron 

 trachycaulum. 



Populus tremuIoides/Poa pratensis 

 Community Type (POTR/POPR c.t.) 



The POTR/POPR c.t. is a serai type that, although 

 not common, spans the State from the Bear River and 

 Uinta Mountains in the north, to the Markagunt Plateau 

 and LaSal Mountains in the south. We sampled 18 

 stands to describe this type, ranging in elevation from 

 7,000 to 9,450 ft (2 130 to 2 880 m) and usually occur- 

 ring on flats or shallow slopes (less than 25 percent) of 

 northerly or easterly exposures. Soil parent material did 

 not appear restrictive. 



The vegetation of this degraded type is relatively sim- 

 ple (fig. 12). It differs from that of the 

 POTR/SYOR/POPR c.t. only in the amount of 

 Symphoricarpos oreophilus. Although S. oreophilus is 

 usually present in the POTR/POPR c.t., it is never suffi- 

 ciently abundant to form a distinct shrub layer. The 

 depauperate undergrowth is dominated by Poa pratensis 

 or Taraxacum officinale or both. Substantial amounts of 

 Agropyron trachycaulum are also frequently present. A 



Figure 12.— The Populus 

 tremuloides/Poa pratensis 

 c.t. is a grazing-induced type 

 dominated by such grazing- 

 resistant species as P. 

 pratensis, Taraxacum 

 officinale, Achillea 

 millifotium, and Trifolium 

 longipes, as in this stand on 

 Webster Flat southeast of 

 Cedar City. Although not 

 common, the type is 

 encountered occasionally on 

 flats or shallow slopes 

 throughout Utah. 



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