536 SOILS. 



The plants which may best serve as such indicators in 

 California are the following: 



Tussock-grass (Sporobolus airoidcs Torr. ), Fig. 82. 



Bushy Samphire (Allcnrolfca occidcntalis ( Wats. ) Ktze. ), 

 Fig. 83. 



Dwarf Samphire (Saliconiia snbtcnninalis Parish, and 

 other species). Fig. 84. 



Saltwort (Sitacda torrcyana Wats., and 6". sitffnitcsccns, 

 Wats.). Fig. 85. 



Greasewood (Sarcobatus vermiculatus (Hook.) Torr.), 

 Fig. 86. 



Alkali-heath (Frankcnia grand if olict cctinpestris Gray), 

 Fig. 87. 



Cressa (Crcssa tnt.rillcnsis Choisy ) , Fig. 88, perhaps 

 identical with C. crctica auct. 



Salt-grass (Distichlis spicata) , Fig. 80. 



TUSSOCK GRASS i Sfrn-oboliis airoidcs, Torr.) ; Fig. 82. 

 ( " Buneh grass" of Xew Mexico). 



The three sets of Tussock-grass soil which have been 

 analyzed show that the total amount of all salts present is 

 in no case less than 40.000 pounds per acre, to a depth of 

 four feet; and that it >ometimes reaches the extraordinarily 

 high figure of 499.000 pounds. Of these amounts the neutral 

 salts i ( dauber's -alt and common salt) are usually in the 

 heaviest proportion i ("dauber'-; salt. K)/H>O to 323,000 pounds 

 per acre; common >alt, 3.500 to 172,800) ; the corrosive sal- 

 soda varying from 3.000 to 44,000 pounds. Tussock-grass 

 .'ipparently cannot persist in ground which is periodically 

 tl ..... led. It is of special importance because it is an acceptable 

 forage for stuck. 



Tussock-gra-> i- a prevalent alkali-indicator in the hot, 

 arid portions of the interior, from the upper San Joaquin 

 Valley, the M<'ja\r desert, .and southward; also through 

 southern Xevada and I'tah as far ea-t as Kansas and Ne- 

 braska. In the San Joaquin Valley it has not been found far- 

 ther north than the Tulare plains, although east of Reno it 

 occurs near Reno. Coville observes that in the Death Valley 

 region "it is confined principally to altitudes below 1,000 

 meters" 13.280 feet). Hillman, however, reports it from 



