INSECT, PLANT DISEASE, & WEED SCIENCE NEWS [No. 87-16] [July 10, 1987]

In This Issue: Late Season Broadleaf Weed Control in Corn and Sorghum Rescue Treatments for Soybeans Prepare Row for Conservation Tillage Rest Year Late Season Broad leaf Weed Control in Corn and Sorghum Corn should not be sprayed with 2,4-D from a week before tassel emergence until after the silks turn brown. Treatments during this critical time often interfere with pollination and cause yield reductions. After the silks turn brown, pollination is complete and 2,4-D use can safely resume. Most corn in Nebraska is now in the stage where it should not be sprayed with 2,4-D. Rescue Treatments for Soybeans Rescue from Uniroyal is a combination of Alanap and 2,4-DB registered for control of escaped sunflower 12 to flower bud and cocklebur 8 to 24 tall in soybeans. Applications should be made after soybeans are 14 tail or first bloom. Crop oil concentrate or a nonionic surfactant should be used with Rescue. Spray pressures of 40 to 50 psi result in better coverage and weed control. Aerial application and spot spraying are also labeled. Under dry conditions, soybeans may wilt and suffer set back by a Rescue treatment. Recovery may not be complete if the weather stays dry. Weeds under dry conditions may not be completely controlled. Prepare Now for Conservation Tillage Next Year Control weeds in small grain stubble this summer for planting wheat in the fall or for 1988 spring planting of corn, sorghum, and soybeans. Advances in chemical weed control make possible the control of weeds and volunteer grain without tillage, Weed control without tillage conserves moisture, reduces wind and. water erosion, and cuts back on energy, machinery, and labor costs