106 SOILS: FBOFEBTIES AND MANAGEMENT 



^/JLT 



JO zo ;jo jiC ^O 60 70 80 -fo woYo 



Fig. 16. — Diagram for the determination of soil class from a mechani- 

 cal analysis. 



79. The significance of texture and class. — Soil 

 texture and class are the basis for all soil consideration, 

 whether regarding some specific property or a general 

 condition such as crop adaptation. No matter what the 

 phase of soil study may be, texture and class are sure 

 to have some important influence and must be included 

 in the investigation. Prom observations in practice, 

 certain crops have been found to be adapted to certain 

 kinds of soil — as clay loam for wheat, silt loam for 

 corn, loam or sandy loam for potatoes, clay or clay loam 

 for timothy, and so on. Two authors ^ have determined 

 the mechanical qualities of soils well adapted to certain 

 crops. An average of their analyses is given below : — 



^Hall, A. D., and Russell, B. J. Soil Surveys and Soil 

 Analyses. Jour. Agr. Science, Vol. IV, Paxt 2, p. 207. 1911. 



