SOILS AND FERTILIZERS 355 



of the soil and the length of the growing season. In the 

 South and Southwest, where four or five or more cuttings 

 may be made in a season and there is an abundant supply of 

 water either from rainfall or irrigation, the yield may vary 

 from 3^ ton to 2 or 3 tons to the acre at a cutting, and the 

 total yield for the season may reach 6 or 8 tons. Where con- 

 ditions are less favorable, the annual yield usually varies 

 from 1 to 3 or 4 tons to the acre. The average yield for the 

 entire country in 1909, as reported by the Census Bureau, 

 was 2.52 tons to the acre. The usual growing season for a 

 crop of hay is from 30 to 40 days, though in warm weather, 

 with plenty of rain, the field may be ready for cutting in 25 

 days from the removal of the previous crop. 



466. Soils and Fertilizers. The soils best adapted to 

 alfalfa are the deep loams, in which the roots can pen- 

 etrate to a considerable depth. A stiff clay subsoil which is too 

 hard for the roots to penetrate is not suitable, while sandy 

 land does not produce growth vigorous enough to keep down 

 weeds. On rich loams a stand of alfalfa, when well estab- 

 lished, will usually crowd out weeds of all kinds. Good 

 drainage is essential, for the plants will not grow with "wet 

 feet." Plenty of water is a necessity for the best growth of 

 the crop, but the plant must be allowed to go after it and 

 bring it up from the lower layers of the soil. 



Although alfalfa will store nitrogen in the soil, it will 

 not thrive on poor land. Some nitrogen must be supplied 

 till the plants get a start and the bacteria begin their work. 

 Good supplies of phosphorus and potash are necessary. 

 When it is thought advisable to use acid phosphate, about 200 

 pounds an acre should be applied. Barnyard manure is 

 the best fertiUzer for alfalfa. If a liberal application of 

 manure is plowed under before the alfalfa seed is sown, 

 there will usually be no trouble in getting a stand. Lime 

 is essential to the growth of alfalfa, particularly to the bac- 

 teria which live on its roots. Unless the soil is known to 



