38 FORAGE CONDITIONS ON NORTHERN BORDER OF GREAT BASIN. 



ally found in the vicinity of the basin-shaped depressions described elsewhere, which 

 have very little vegetation aside from this plant. 



Delea {Delea kingii) . — On the sand hills about 20 miles north of TVinnemucca, 

 this is the only plant which is able to sustain itself in rapidly shifting sands. It 

 usually grows sparingly but evenly over large areas, propagating rapidly by its long 

 slender reddish rootstocks, which may be easily pulled up out of the loose sand 

 through which they ramify. The spinescent branches, the yellowish-green coloration 

 of the leaves, the reddish rootstocks, and the purple flowers give this plant a very 

 characteristic and striking appearance as it spreads over freshly formed hillocks and 

 mounds of sand. 



Tetrad ymia ( Tetrad i/m ia comosa ) . — Large bushes of this were found in abundance in 

 the same vicinity as Dalea Idngii. Almost invariably they were situated upon 

 moimds or half buried hi the sand, indicating that the soil had been removed from 

 the surrounding areas or had been piled on top of the plants. PI. VII, fig. 2, illus- 

 trates the effectiveness of this plant in preventing the sands from drifting. 



Moss ( Tortula ruralisf). a — It is with considerable hesitancy that a moss is recorded 

 as a sand binder, but that this species serves this useful purpose over quite extensive 

 areas in northern Nevada and eastern Oregon is perfectly apparent to anyone visiting 

 the region between June and October. This small plant does not grow over the 

 entire mesa, but, on the contrary, is confined to circumscribed areas immediately 

 beneath and immediately surrounding shrubby plants, such as black sage, spiny 

 saltbush. tetradymia, and the shad scale. Its period of growth is evidently late 

 winter and early spring, at which time it forms a complete covering for the ground. 

 When conditions of drought appear it dries up completely, and. while easily removed 

 from its position, it forms mats which catch the sand that blows into it, and serves 

 in this way to enlarge the small mounds which appear surrounding the desert shrub- 

 bery. Every area of this plant examined was almost completely imbedded in sand. 

 That it grows in this way is not at all likely, because an abundance of leaves were 

 always found below the surface of the sand, indicating that the plant had been cov- 

 ered after the advent of dry weather in late spring and early summer. 



Besides the plants mentioned above, many others might be named 

 in this connection. The sandy area on the south and east of the 

 Alvord Desert in southern Oregon showed a very marked influence of 

 some of the common desert shrubs upon shifting sands. Among 

 plants which acted as sand binders in this locality and were almost 

 invariably found in hillocks of sand may be mentioned the spiny salt- 

 bush, shad scale, and the black sage. 



WEEDS. 



It will be noticed that this short account gives special prominence 

 to native plants which occur to such an extent as to be classed weeds. 

 This is not at all to be wondered at in a region so little improved as 

 the one in question, and. in a region where the preponderance of the 

 crops on both pasture and hay lands are harvested on the unfilled 

 ground, and consist of native plants which receive no other care than 

 that of harvesting. Under conditions where the pasture and hay 

 lands are taxed to their full capacity, the fact that some plants which 

 are not relished by cattle increase to an unsightly or even alarming 



determined by Mrs. E. G. Britton. 



