Table 7. Sorghum yields in relation to date of planting (DOP),
harvest date (HD), irrigation (I), and problems (BD=bird damage,
M=midge) for decision-making in single- or double-cropping
systems.


 Funks Funks Funks Funks Funks Funks
 G 522DR G 522DR G 522DR G 522DR G 522DR G 522DR

 DOP 4-14-81 5-18-81 6-5-81 7-13-81 7-28-81 8-11-81

Rep bu/A

 I 102 68 43 112 102 71
 II 103 64 49 106 104 73
III 105 72 41 103 108 78
IV 104 72 43 107 105 74

Mean 104 69 44 107 106 74

Problems:

BD 8/27 9/28 10/8 10/8
M 7/21
I none none none Irr Irr Irr
HD 7/28 8/18 9/14 11/6 11/23 11/25




 Yield, cost, price, and net return for single- and double-

crops are shown in Table 8. To calculate returns from double-

cropping, add the net returns of the two crops selected.

Double-cropping reduces production costs of the following-crop

because it can utilize residual fertility from the previous crop.