SWEET CLOVER: UTILIZATION. 31 



alternated with each other. The 4-year average weight of green 

 matter produced on the sweet-clover plat was 14f tons per acre, 

 whereas the 5-year average weight of green matter produced by 

 common vetch and Canada field peas was 12 tons and 9 tons, re- 

 spectively, per acre. On one series of these plats corn was planted in 

 rotation with the clover. The average yield of shelled corn for four 

 years was 46 bushels to the acre on the sweet-clover plat, as compared 

 with 35 bushels to the acre on the common-vetch plat and 40 bushels 

 per acre on the field-pea plat. One barley plat receiving each year an 

 application of 1,080 pounds of nitrate of soda gave an average yield 

 of 41 bushels pec acre. The 2-year average yield of potatoes follow- 

 ing sweet clover was 252 bushels per acre, as compared with 171 bush- 

 els following common vetch and 234 bushels following field peas. 

 Sweet clover has proved to be an excellent plant to grow in rotation 

 with sugar beets, as the 2-year average for the beets following it 

 was 19.8 tons per acre, as compared with 15.3 tons following common 

 vetch, and 17.6 tons following field peas. 



Annual yellow sweet clover makes a profitable growth only in the 

 South and Southwest and therefore should not be planted in any 

 other section of the country. 



In those sections of the United States where the soils are low in 

 humus it is to be strongly recommended that sweet clover be grown 

 for green manure. This method is being practiced in some sections 

 of the country with excellent results. 



It should be remembered that sweet clover will not make a satis- 

 factory growth on acid soils and that it is very essential to provide 

 inoculation if the soil is not inoculated already. 



SWEET CLOVER IN ROTATIONS. 



As sweet clover is a biennial plant, it lends itself readily to short 

 .rotations. It may be seeded in the spring on winter grain or with 

 spring grain, the same as red clover. It will produce at least as much 

 pasturage the following fall as red clover, and in some parts of the 

 country a cutting of hay may be obtained after the grain harvest. The 

 following year the plants will produce two cuttings of hay or one cut- 

 ting of hay and a seed crop. In some sections of the United States 

 this plant is replacing red clover in rotations, as it will succeed on 

 poorer soils than red clover and will add much more humus to the 

 soil. It will withstand drought better than either red clover or 

 alfalfa, and on this account its use in rotations may be extended into 

 drier sections. As a rule the beneficial effect of sweet clover on the 

 subsequent crops is more marked than that of other legumes. This 

 is especially true with corn, and whenever possible corn should follow 

 sweet clover in rotations. Root crops also are benefited by its use 

 in rotations, as the large deep roots of sweet clover open up the soil. 



