whose main distinctions are between prairie, conifer woodland, 

 hardwood stands, and sparsely-vegetated settings. 



The vegetation of the District has otherwise been described in 

 terms of areas with unigue vegetation (USDA Forest Service 1976) , 

 exlosure studies, Research Natural Area establishment records, and 

 other site-specific studies. Unigue vegetation types that were 

 identified include areas with peripheral species such as paper 

 birch (not dominant but as local component of other plant 

 associations) , "relict" grasslands on isolated butte settings 

 inaccessible to livestock, areas having some level of "high value 

 botanical communities" as identified by Van Bruggen (USDA Forest 

 Service 1975), and sites harboring "rare or endangered plants". 



Mixed grass prairie is the matrix in which other vegetation types 

 are included, depending on slope, aspect, topographic position, 

 rockiness, parent material and localized hydrological factors. 

 Mixed grass prairie is prevalent on exposed escarpment slopes, on 

 the level butte tops and on the plains surrounding escarpments. It 

 is dominated by a mixture of mid and short grasses. These include 

 habitat or community types dominated or with major components of 

 Stipa comata, Carex filifolia , Carex heliophila , Bouteloua 

 gracilis , Koeleria macrantha , Poa sandbergii and Agropyron smithii. 

 Rosa arkansana is a freguent shrub, with Gutierrezia sarothrae and 

 Artemisia spp. in some places. A^_ cana is prevalent along lower 

 valley stream terraces. Forbs are normally scattered individuals, 

 typically Artemisia ludoviciana , Ratibida columnifera . Phlox 

 hoodii , Polygala alba , and Erigeron pumilus . 



The steep, south-facing slopes are covered by little bluestem 

 prairie dominated by warm-season grasses. The soil is usually 

 sandier, more gravelly, and often rocky. The vegetation is 

 dominated by Andropogon scoparius , Calamovilfa longifolia and 

 Agropyron spicatum , with varying amounts of Muhlenbergia cuspidata 

 and Bouteloua curtipendula . Anemone patens is a typical forb. 

 Under Agropyron spicatum dominance, the grass cover decreases, 

 consisting primarily of clumps separated by open areas, where forbs 

 become more freguent. The latter include Echinacea angustifolia , 

 Helianthus rigidus , Dalea spp. , Solidago missouriensis , and on the 

 more open, gravelly slopes Phacelia hastata, Lesguerella alpina , 

 Ipomopsis congesta, and Senecio canus . The shrub Rhus trilobata is 

 locally dominant, and patches of Prunus virginiana and Amelanchier 

 alnifolia are common. In many places little bluestem prairie 

 grades into a Pinus ponderosa forest above it. 



The greatest proportion of the Long Pines and Ekalaka Hills are 

 covered with Pinus ponderosa woodland and forest. These vary from 

 scattered trees on south-facing slopes, with an understory of 

 species usually found in little bluestem prairie, to denser forests 

 on more level terrain on mesa summits, with very little understory, 

 and a thick litter layer. On some ridge tops Thermopsis 

 rhombifolia is the dominant forb. 



