28 The Bulletin 



The most important objects of a cover crop are : 



1. To add nitrogen and plant food. 



2. To add luimus, which makes the soil more retentive of moisture. 



3. To prevent washing and leaching, and thus preserve the fertility 

 of the soil. 



4. To check fall growth by using available moisture. 



5. To improve the physical condition of the soil. 



There are two types of cover crops: the legumes, such as cowpeas. 

 soybeans, crimson clover, vetch, and bur clover; and the non-legumes, 

 the chief of which is rye. Legaimes are plants that take nitrogen 

 from the air and add it to the soil, while non-legumes are plants that 

 use the available nitrogen in the soil, and serve to hold it over until 

 the next season. The legumes should be inoculated with nitrogen- 

 fixing bacteria, if the ground has not within recent years grown the 

 particular legiime that the orchardist desires to use. Inoculation of 

 the seed insures a lar2:er and more uniform stand. 



Fig. 19. Young orcliard in Sand Hills witli cowpeas drilled between rows as a cover crop. 



Cowpeas and soybeans are in most general use in this State as soil 

 improvers and cover crops. In young orchards, cowpeas or soybeans 

 are put in drills in June and tillage of both peas and trees continued 

 with a .small cultivator until about the first of August or until growth 

 of the peas prevents further tillage. When peas are drilled in young 

 orchards, a clean strip 4 to (^ f<'ot Avide is left on each side of the 

 tree rows. In bearing orchards, cowpeas or soybeans are either drilled 

 or broadcasted in -Tnly, generally after the middle of the montli. The 

 cowpeas are sccdod at the rate of from 1 1o 2 bushels, iiiid soyheaiis 

 at tlif rate of from 1 {, to 1 bushel, depending on whether they are 

 drilled in or broadcasted. The first severe frost kills the cowpeas, and 

 because of this, some growers plow them under in the fall and imme- 

 diately sow rye to er>ver the ground during the winter. Other orchard- 



