B, Large mountain brome grass (Bromus marginatus) . La, Evening primrose (Lavauxia flava) . PI, Plantain (Plantayo tweedyi). 



Ch, Lamb's-quarter {Chenopodium album). Pg, Douglas knotwc-ed (Polygonum douglasii). So, Tansy mustard (Sophia indsa). 



H, Mountain squirrel tail (Hordeum nodosum). R, Mexican dock (Rumex mexicanus). V, Tongue-leaved violet (Viola linguacfolia). 



Fig. 25. — Old denuded bed ground abandoned in 1912, showing character of vegetation in 1917. 

 112655°— 19. (To face page 61.) 



