I4i8 



METHODS OF SOn, CUI^TIVATION 



Table I. — Relation of per cent of crop area in intertilled crops to crop index 

 in Chester Co. Pa. (1914 survey). 



(i) An animal unit is a mature horse or cow or as many smaller animals as reqxiire the feed of a 

 horse or cow, i. e., 2 head of young cattle; 5 hogs, 7 sheep, or 100 hens. 



Tabi^E II. — Relation of per cent of crop area in intertilled crops to crop index 

 in Central Illinois (1913 survey). 



Table III. — Relation hetiveen the per cent of the crop area in annual crops 

 not intertilled and crop index in Chester Co. Pa. (1914 survey). 



