Agronomy and Horticulture Department


Date of this Version



Insect Science, Plant Disease, & Weed Science, University of Nebraska Cooperative Extension, Institute of Agriculture and Natural Resources 88(13) (June 24, 1988).


Copyright 1988 University of Nebraska.


In This Issue:

  • Late Season Broadleaf Weed Control in Corn and Sorghum
  • Rescue Treatments for Soybeans
  • Prepare Now for Conservation Tillage Next Year

Late Season Broadleaf 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. The early planted corn in Nebraska is now in the stage where it should not be sprayed with 2,4-D.

Rescue Treatments for Soybeans

Most broadleaf weeds taller than 6" cannot be consistently controlled in soybeans with postemergence herbicides. There are no soybean herbicides that perform like 2,4-D and Banvel.

Prepare Now for Conservation Tillage Next Year

Control weeds in small grain stubble this summer for planting wheat in the fall or for 1989 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 (which is critical this year), reduces wind and water erosion," and cuts back on energy, machinery, and labor costs. Successful chemical weed control requires consideration of certain basics:

1. Straw and chaff behind the combine should be uniformly spread-if not, bale it. Excess straw and chaff interferes with herbicide performance and planting the next crop.

2. A poor job of combining will contribute to poor herbicide performance. Heavy stands of volunteer grain are likely to strain herbicide capabilities.