37 



has observed the roots of alfalfa at 25 feet (7.6 m.O 1 

 and mentions depths of 60 feet (18 m. ) as "credibly- 

 reported". The same author records vine and fruit tree 

 roots at 20 feet (6 m. ) 2 and roots of sagebrush 

 (Artemisia) and salt bush (Atriplex) at the same depth**. 

 Hop vine roots were found at 10 feet (3m.) and roots 

 of two native California plants ( Ghenopodium califomicum 

 and Scrophularia californica ) at 11 feet 2 inches (3.4 m. ) 

 and 10 feet 6 inches (3.2 m. J , respectively . Cannon has 

 observed of mesquite ( Prosopis velutina ) at 5 nu and men- 

 tions them as reported at 8 m. Many desert perennials 



1. Soils, p. 229 (1906). 



2. I.e., p. 231. 



3. I.e., p. 230. 



4. I.e., pp. 171-172. 



5. Hilgard,- Soils, pp. 173-174 (1906). 



6. Car. Inst, of Wash., Pub. 131 . pp. 80, 92 

 (1911); Car. Inst, of Wash., Yearbook, 12: 72 (1913). 



