-5- 



Here's a handy reminder: two miles of fence row that is four feet wide equals about 

 an acre. 



DOUBLE-CROPPING STRATEGY 



Plan your strategy for planting soybeans in wheat stubble now, so you'll be ready to 

 spray and plant immediately after harvesting the wheat. Spraying and planting imme- 

 diately allows more time for the soybeans to grow and also produces better weed con- 

 trol. 



Lorox, used with an appropriate surfactant to improve postemergence control, is the 

 major compound used for weed control in double cropping. The trick is to keep the 

 Lorox rate high enough for the postemergence effect, but low enough to avoid soybean 

 injury. If the weeds are small and conditions are favorable, two pounds of Lorox 50W 

 plus a surfactant should be adequate for postemergence control. 



The stubble and weeds will intercept some Lorox, so you can't be certain how much of 

 the herbicide will actually reach the soil . You may need to use one to two pints of 

 Paraquat plus a surfactant to improve the control of existing weeds , especially if 

 they are more than five or six inches tall . 



If you anticipate a problem with annual grass weeds, consider adding about two quarts 

 of Lasso per acre. Amiben, Amilon, and other herbicides represent other possibilities. 



You can expect a considerable range in yields from soybeans following wheat, depending 

 primarily on the amount of rainfall during the season. In good years, yields may be 

 20 to 30 bushels or more per acre. Otherwise, the yields may be only 10 to 20 bushels, 

 or the crop may even be a complete failure. One agronomist estimates that the break- 

 even yield for soybeans as a second crop is about eight bushels per acre. 



Planting soybeans after wheat is an excellent way to help control weeds in the stubble. 

 Doing this allows you to use the energy from sunlight, nutrients, and moisture for an 

 extra two to three months for increased crop production. 



CONTROLLING WEEDS IN SMALL-GRAIN STUBBLE 



Results from a long-term field study at Urbana suggest that you can reduce the weed- 

 seed supply in the soil by doing a good job of controlling weeds in corn and soybeans. 

 But if you let foxtail, johnsongrass, ragweed, or others produce seed in small-grain 

 stubble, you're replenishing the supply of weed seeds in the soil. 



If there is no underseeding of desirable legumes and grasses in the stubble, consider 

 spraying with a mixture of dalapon and 2,4-D to control the grasses and the broadleaf 

 weeds. The rate to use will depend on the kinds and sizes of the weeds. 



Dalapon at two to three pounds per acre may control foxtail that is only a few inches 

 high. However, johnsongrass may require five to seven pounds per acre; also, repeated 

 treatments. For easy-to-kill broadleaf weeds, a fourth to a half a pound per acre of 

 2,4-D may do the job. For tougher weeds, you might need a half to a pound per acre of 

 2,4-D. 



One of the most effective and practical programs to take care of johnsongrass is to 

 treat with dalapon after small-grain harvest, to control old plants and rhizomes, then 

 follow up in the spring with Treflan and soybeans for seedling control. Refer to the 

 dalapon label and Illinois Circular 827 for details. 



