340 NATURE AND PROPERTIES OF SOILS 



fered in this way, and not infrequently they have reverted 

 to a desert state. 



179. Alkali vegetation. — There are a great number of 

 plants that seldom grow on soils other than those affected with 

 alkali. Davy 1 states that there are 197 species restricted to 

 alkali soils in California. Such plants are generally recog- 

 nized by the farmers in the district as indicators of alkali. 

 Care should be taken, however, in thus classifying alkali land. 

 Such plants should occupy the land to the exclusion of less 

 tolerant species. Some of the plants 2 whose presence should 

 cause one to surmise alkali conditions are as follows : 



Greasewood Inkweed 



Alkali-heath Tussock-grass 



Salt-grass Bushy samphire 



Salt-bush Spike-weed 



Cressa Rabbit bush 



Sage-brush, which is so often associated in popular literature 

 with alkali, does not grow on land which carries a great amount 

 of soluble salts. In locating land it is, therefore, a good indi- 

 cator of alkali-free conditions, especially if it is growing vig- 

 orously. 



180. The handling of alkali lands. 3 — Ordinarily there 

 are two general ways in which alkali lands may be handled in 

 order to avoid the injurious effects of soluble salts. The first 

 of these is eradication, the second may be designated as con- 

 trol. In the former case an attempt is made actually to elimi- 



1 Davy, J. B., Investigations on the Native Vegetation of Alkali 

 Lands; Calif. Exp. Sta. Kep., 1895-97, pp. 53-75. 



2 Harris, F. S., Soil Alkali; Chap. VI,* New York, 1920. 



"Dorsey, C. W., Reclamation of Alkali Soils; U. S. Dept. Agr., Bur. 

 Soils, Bui. 34, 1906. Also, Hilgard, E. W., Utilization and Reclamation 

 of Alkali Soils; New York, 1911. Also, Brown, C. F., and Hart, E. A., 

 Reclamation of Seeped and Alkali Lands; Utah Agr. Exp. Sta., Bui. Ill, 

 1910. Also, Dorsey, C. W., Reclamation of Alkali Soils at Billings, 

 Montana; U. S. Dept. Agr., Bur. Soils, Bui. 44, 1907. Also Harris, 

 F. S., Soil Alkali; Chaps. XII, XIII and XIV; New York, 1920. 



