FOOD REQUIREMENTS OF CROPS 26 1 



On some soils, however, wheat does not thrive following 

 a sod crop, as it takes nearly a year for a heavy sod 

 residue to get into suitable food forms for a wheat crop, 

 and under such a condition, oats should first be sown, 

 then wheat may follow. On average soil, a medium 

 clover sod, plowed late in summer or in early fall, and 

 followed by surface cultivation, leaves the land in good 

 condition for spring wheat. It is not advisable to have 

 wheat follow barley, because the soil will be too porous, 

 and barley being a stronger feeding crop leaves the land 

 in a poor state as to available plant food. When corn 

 has been well manured, wheat may follow. The food re- 

 quirements of wheat are best satisfied following a light, 

 well-cultivated clover sod, or following oats, which have 

 been grown on heavy sod, or following corn that has 

 been well manured. When wheat is judiciously grown 

 in a rotation and farm manures are used, it is not an ex- 

 hausting crop. Light dressings of farm manure may 

 be used on land that is being prepared for wheat. On 

 many western prairie soils, dressings of phosphate and 

 potash, either alone or in combination, materially increase 

 the yield and improve the quality of the crop. Potash 

 fertilizers have a tendency to produce strong bright 

 straw that is more resistant to fungous diseases. Nitro- 

 gen alone does not give as good results as when com- 

 bined with minerals. 



311. Barley. --While wheat and barley belong to the 

 same general class of cereals, they differ greatly in their 



