FAMILIES OF PLANTS 
35 
Poa nervosa 
Poa nevadensis 
Poe painstris 
Poa pattersonii 
Poa pratensis 
Poa reflexa 
Poa rupicola 
Poa secnnda 
Puccinellia . nuttalliana 
Schedonnardus paniculatus 
Schizachne purpurascens 
Sit anion hystrix 
Spartina gracilis 
Stipa columbiana 
Stipa columbiana var. nelsonid 
Stipa comat a 
Stipa comata var. intermedia 
Stipa lettermanii 
Stipa occidentalis 
Stipa richardsonii 
Stipa viridula 
Stipa williamsii 
Trisetum spicatum 
Trisetum wolfii 
Triticum aestivum 
Figure 18.—Giant wild-rye. Photograph by Dr. Harvey E. Stork. 
SEDGE FAMILY (CYPEEACEAE) 
This is a large family and there are undoubtedly many more repre¬ 
sentatives in the park than have been identified. Much of the grass¬ 
like vegetation above timberline is composed largely of sedges, and 
there are also many species that occur below timberline. Most of the 
park visitors include these plants with the grasses and pay no particu¬ 
lar attention to them. They can usually be distinguished from the 
grasses, however, by the three-angled stems, the absence of joints on 
the stems, and by the fact that the leaf bases form tubes about the 
