pied by a distinctive array of perennial herbs. These meadows sup- 

 port the Montane Meadow plant community, which is character- 

 ized by a variety of perennial grasses, sedges, and a number of low, 

 broad-leaved herbs. Also present is the tall, striking Corn Lily 

 (Veratnim califomicum). In mid- to late summer, the wildflower 

 displays in these meadows are often very colorful. Because of 

 the irregular distribution of this plant community, it was not in- 

 cluded in the maps. 



Alpine Fell-field (Plate 13B-D) 



Despite the ability of pines and other conifers to survive and 

 even prosper under the unfavorable environmental conditions at 

 high elevations, there is a point of elevation at which the climatic 

 regime is too stringent for successful growth of trees of any kind. 

 The point at which this ecological circumstance develops is called 

 timberline and is marked by a sharp reduction in number and 

 size of trees. Above this zone of dwarfed and stunted trees is 

 another plant community which occupies very high elevations in 

 the mountains. This is the Alpine Fell-field plant community, a 

 community of low perennial plants that occurs above 9,500 feet 

 (2,896 m) in the Sierra Nevada (primarily), and also in parts of 

 the Cascades and the San Bernardino and San Jacinto mountains. 

 Precipitation in the Alpine Fell-field occurs mostly as snow in 

 the winter, since the elevation is above the point of maximum 

 rainfall on the slopes of the mountains. In many respects, this 

 plant community occupies an alpine desert. The growing season 

 is less than two months long — sometimes as short as six weeks — 

 and heavy frosts may occur during almost any night of the sum- 

 mer. The appearance of this plant community is much like that 

 of a rock garden. The rock-strewn peaks, slopes, or open fields 

 are frequently covered by masses of perennial herbs that form a 

 low, dense turf. Many of the plants in these areas form small 

 cushionlike mats with densely packed leaves. A few grass and 

 sedge species occur in the Alpine Fell-field, but these are accom- 

 panied by a large variety of dicots belonging to diverse genera 

 in several families. Many of the dwarfed inhabitants of the Al- 

 pine Fell-field (such as the crucifers, composites, penstemons, 

 phloxes [Plate 13C] , wild buckwheats [Plate 13D] , and 



105 



