144 



THE PEANUT— THE UNPREDICTABLE LEGUME 



satisfactory kernel development, it is essential that calcium be supplied to 

 the zone in which fruit are being formed. 



The best method of applying gypsum to peanuts appears to be that of 

 dusting the material on the plant at the early flowering stage. This rela- 

 tively soluble source of calcium falls around the plant in the zone of pod 

 formation and is present at the time when the need for calcium is the 

 greatest. It is essential that the gypsum be well distributed throughout the 

 zone of fruit formation. Since there is little residual efifect of normal 

 applications of gypsum (300 to 600 pounds per acre), it is necessary to 

 make annual additions of this material. 



Table 6. — Effect of Placement of Gypsum on Yield and Quality of Peanuts 

 ON Norfolk Fine Sandy Loam, Deep Phase, in 1942». (45) 



* Four replications 



•> Rate = 400 pounds per acre. 



As shown in table 5, broadcast applications of lime may be as effective 

 as gypsum in meeting the calcium requirements of peanuts. However, 

 these and other data (18, 37, 45) generally indicated that lime applied in 

 the row at planting may be inferior to gypsum. A satisfactory plan might 

 be one in which 1,000 to 1,500 pounds of lime are applied broadcast to 

 the peanuts every 2 to 4 years, the exact amounts and frequency of ap- 

 plications being governed by soil characteristics. It would appear to be 

 best to broadcast the lime after the land had been turned but before the 

 peanuts are planted. By so doing, more of the calcium is concentrated in 

 the surface layer and hence should be more effective in supplying the 

 needs of the developing pods. By applying relatively small amounts of 

 lime in this manner immediately prior to peanuts in the rotation, it might 

 be possible to maintain an adequate supply of calcium without increasing 

 the pH beyond the level where certain minor-element deficiencies are en- 

 countered. 



