EFFECT OF GRAZING . ON" WESTERN YELLOW PINE. 5 



Reproduction is abundant and well distributed and on account of 

 the longer growing season growth is more rapid here than on the 

 Deadwood area. On the sample plots 58 per cent of the seedlings 

 were western yellow pine, 34 per cent Douglas fir, and 8 per cent 

 lowland white fir. 



The undergrowth on this allotment is dense and fairly evenly dis- 

 tributed; browse predominates. Its forage value is much higher 

 than that on the Deadwood area because of its greater density and 

 the larger proportion of palatable species. 1 



THE SOUTH FORK ALLOTMENT. 



The South Fork allotment represents the best western yellow pine 

 land in this region. Except for the main ridges, which reach 6,000 

 feet, most of the area is between 3,800 and 5,000 feet in elevation. 

 Western yellow pine trees here occasionally reach a height of 190 

 feet. Western yellow pine makes up from 70 to 100 per cent of the 

 volume of the stand, which probably averages for the entire area 85 

 per cent pine and 15 per cent Douglas fir. 



The forage cover is denser and more palatable than that on either 

 of the other two areas. Even on the south slopes there are few of 

 the bare spots such as are common on the Deadwood allotment, but 

 there are more brush areas so dense that they can not be utilized. 

 Browse is the predominant type of forage, except on south slopes, on 

 which grasses and weeds predominate. 2 



METHOD OF STUDY. 



Small sample plots were chosen in such a way that they were well 

 distributed over the three grazing allotments and were so located as 

 to cover the greatest possible variety of conditions of topography, 

 stand, forage cover, and use of the range. They are believed, there- 

 fore, to represent fairly the western yellow pine type of forest in the 

 region described. 



Thirty-nine plots were studied for the last year only, 40 more for 

 two seasons, and 72 more for three years, a total of 151 plots with an 

 aggregate area of approximately 75,000 square feet. 



1 Characteristic plants are: Ceanothus ( C. velutinus and C. sanguineus), ninebark (Opulaster malvaceus), 

 huckleberry ( Vaccinium membranaceum), choke cherry (Padus demissa), willows (Salix spp.), spiraea 

 (S. lucida), snowberry (Symphoricarpos rotundifolius) , rose (Rosa spp.), pine grass ( Calamagrostis rubescens), 

 silver dock (Balsamorrhiza sagittata), fireweed ( Chamaenerion angustifolium) , geranium (G. incisum), brome 

 grass (Bromus marginatus), and meadow rue ( Thalietrum occidental). 



2 Characteristic plants are wheat-grass {Agropyron spicatum ), June grass (Koeleria cristata), blue bunch- 

 grass (Festuca idahoensis), brome (Bromus marginatus), blue grass ( Melica sp. and Poa sp.), ceanothus 

 (C. sanguineus and C. velutinus), ninebark (Opulaster malvaceus), snowberry (Symphoricarpos rotundi- 

 olius), spiraea (S. lucida), rose (Rosa spp. ), willows (Salix spp.), service berry (Amelanchier alnifolia), 

 mountain ash (Sorbus sambucifolia), maple (Acer glabrum), buck brush (Kunzia tridentata), syringa (Phila- 

 delphus lewisii), silver dock (Balsamorrhiza sagittata), asters (Aster spp.), geranium (G. incisum), sun- 

 flower (Helianthella sp.), pea-vine (Lathy rus spp.), lupine (Lupinus spp.), wild carrot (Leptotaenia sp.), 

 fireweed ( Chamaenerion angustifolium), hellebore ( Veratrum sp.), brake (Pteridium aquilinum pubescens), 

 nad meadow rue ( Thalic'rum occidentale). 



