3.3 VEGETATION TYPE DESCRIFTICKS 



3.3.1 Literature Reviev; 



Vegetaticxi ccrmiunities of the Svveet Grass Hills have been mapped and 

 described in very general terms during several statev/ide efforts. Ptoss 

 and Hunter (1976) utilized the USDA Soil Qxservation Service range 

 site irethodology to rrep climax vegetation of Kicntana based oi soils apd 

 climate. In the &.-.eet Grass Hills, upper elevation sites v;ere irejped 

 as a forest-grassland cocrplex in the. 15 to 19-inch precipitaticn zone 

 en shallow to moderately deep soils with a frigid tenperature regime. 

 Species occurring en forested sites include Douglas-fir, sncwberry, 

 spixea, Oregcn grape and Idaho fescue. Grassland species listed were 

 Idaho fescue, bluebunoh vrf-eatgrass, Columbia needlegrass, lupine and 

 arrowleaf balsamroot. Foothills surrounding the forest grassland 

 ccrrplex were mapped as a silty range site, also in the 15 to 19-inch 

 precipitaticn zcre. Dominant species listed for this rrepping unit 

 jLnclude rougi^ fescue, Idaho fescue and bluebunch wheatgrass. The 

 prairie surrounding the Sweet Grass Hills vras mapped as a silty-clayey 

 range site ccnplex in the 10 to 14-inch precipitaticxi zone of the 

 Western Glaciated Plains Geograj^iical Area. This range site occurs 

 across much of northHcentral Montana, frcm v.'sst of Shelby to near 

 Havre. Dominant species en silty sites include needle-and- thread, 

 western and thickspike wheatgrass, green needlegrass, bluebunch 

 wheatgrass, prairie junegrass, blue grama and several forts. Similar 

 species corpositicn is listed for the clayey range site, although 

 relative abundance v.ould be expected to differ frcm silty sites. 



11 



