58 A Study of the Vegetation of 



yellow blossoms, their great numbers, often more than 100 indi- 

 viduals in a square meter, give a distinct tone in contrast to the 

 gray background of dead vegetation. 



Later on by the blossoming of Amelanchier, Crataegus, Prunus, 

 and Rosa especially, the developmental shrub community be- 

 comes very conspicuous. But the prairies become veritable 

 flower gardens during the month of June. Then the large red 



FIG. 15. Hu, Heuchera glabella. A, Astragalus arrectus. S, Sidalcca 

 oregana. H, Helianthella douglasii. Ag, Agropyron spicatum. 



blossoms of Geranium and Rosa mingle with the yellow of Poten- 

 tilla, Gaillardia, Castilleja, and Helianthella. Senecio, Astragalus, 

 Arnica, and societies of Wyethia brighten the landscape with their 

 yellow blossoms, while the tall, widely spaced, sentinel-like plants 

 of Cirsium foliosum with their showy red flowers add pleasing 

 variety. 



Likewise the purple flowers of various lupines are conspicuous. 

 Lupinus wyethii is only locally abundant. It is especially no- 

 ticeable in the vernal aspect. It often covers areas of the driest 

 hillsides and the whole aerial part dries up early. Lupinus or- 

 natus is very cosmopolitan over the high prairies and is an im- 

 portant species. Lupinus sericeus is confined to the warmer 



58 



