82 



PRINCIPLES OF FARM PRACTICE 



Cultivation. If the seed bed is properly prepared, there 

 will be a good mulch with which to start. The chief object 

 of cultivation is to maintain this mulch in its original 



effective condition. The 

 first cultivation may be 

 made with a harrow, for 

 if care be taken, it does 

 not injure the corn 

 even though it has reached 

 a height of three inches. 

 Later, a cultivator 

 adapted for such work 

 should be used. The first 

 cultivation may be 

 rather deep. After that, 

 by using a cultivator with 

 small teeth the cultiva- 

 tion will be shallow 

 enough to avoid injuring 

 the roots of the plants. 



The number of culti- 

 vations depends upon the 

 season. Experiments 

 have demonstrated that 

 more than four for an 

 entire season will not 

 usually increase the yield. 

 During the early part of 

 the season it is desirable to cultivate after each rain as 

 soon as the condition of the soil permits. Where a good 

 mulch is maintained by frequent cultivation weeds are 

 incidentally kept under control. In rainy seasons, the pre- 



Life-history of the chinch bug. 



a- Egg. 



b, c, d, e. Developing stages. 

 /. Adult. 



g. Eggs at base of leaf of plant. (Hase- 

 man, Missouri Agr. Exp. Station.) 



