CLOVER IN ROTATION 345 



seed from the hulls. The usual yield is but 1 or 2 bushels 

 to the acre, though 5 bushels is sometimes obtained. The 

 usual price for clover seed is from $5 to SIO a bushel of 60 

 pounds, though in 1918 it sold as high as $20 a bushel. 



456. Place in the Rotation. Clover occupies a prominent 

 place in the rotation throughout the region where it is grown. 

 It usually follows a small grain crop and precedes corn or 

 potatoes. As has previously been stated, it is generally 

 sown with winter wheat or with some one of the spring grains. 

 Where corn is an important crop, the common rotation is 

 a 3-year one of wheat, clover, corn or oats, clover, corn, 

 though two crops of corn may be grown in succession, making 

 a 4-year rotation. Where potatoes are largely grown, a com- 

 mon rotation is potatoes, oats, clover. Sometimes the clover 

 is left for two years, or two crops of potatoes or one of pota- 

 toes and one of corn are grown, making this a 4-year instead 

 of a 3-year rotation. In any case, clover is depended on to 

 add vegetable matter and nitrogen to the soil. Where it 

 is grown as often as once in three years, this element need 

 not generally be purchased, but potash and phosphorus will 

 have to be added either in commercial fertilizers or barn- 

 yard manure, unless the soil is very rich in these constitu- 

 ents. Best results are usually obtained when the manure is 

 applied to the clover sod before breaking it up for corn. 



457. Enemies of Red Clover. The most common fun- 

 gous diseases which attack the clover plant are leaf spot, rust, 

 stem rot, and root rot. These diseases seldom do serious 

 injury to a vigorous stand, but on poor land or elsewhere 

 under conditions where the plant does not thrive they may 

 cause serious injuiy. The best remedies are to improve the 

 condition of the soil by adding fertility or by draining, and 

 to practice a proper rotation of crops. 



Insects usually do far more damage to clover than dis- 

 eases. Among the more common enemies are the clover-root- 

 borer, the clover-leaf weevil, and the clover-fiower midge. 



