32 SOILS 



7. That wheat is most at home in soils where fine silt 

 and clay predominate. 



8. That grass fancies most those soils that carry a 

 high percentage of clay. 



9. That potatoes prefer a sand type where medium sand 

 prevails, where silt is present in a medium quantity, and 

 where clay is present only in moderate quantities. 



10. That with these special types must be included 

 good tillage, humus, air, moisture, and plant food. 



Soil type standards. It is out of the range of possi- 

 bilities to give definite standards of soil type for specific 

 crops : too many conditions prevail, such as previous 

 treatment of the land, climate, plant food, humus content, 

 soil drainage, tillage methods, etc. The following stand- 

 ards are suggested in the light of known conditions in a 

 very general way : 



1. Early truck and potatoes : 



Not more than 15 per cent, of water. 

 As much as 60 per cent, of medium sand. 

 Not more than 10 per cent, of clay. 

 About 20 per cent, of silt. 



2. Late truck and fruit: 



Not more than 20 per cent, of water. 



As much as 50 per cent, of medium and fine sand. 



Not more than 25 per cent, of clay. 



From 10 to 30 per cent, of silt. 



3. Corn : 



An average of 20 per cent, of water. 



Not more than 50 per cent, of medium fine and very fine 



sand. 



Not more than 20 per cent, of clay. 

 From 15 to 25 per cent, of silt. 



