Weed Control for Early Harvested Fields Going in to Small Grains

Mark VanGessel, Extension Weed Specialist; mjv@udel.edu

I have been asked about options for corn fields that are being harvested early, will be sprayed with glyphosate for perennial weed control, and then will be planted to wheat. Growers are looking for options to keep these fields “clean” from the glyphosate application until wheat planting. There are not many options, with only Sharpen, Finesse, or Valor labeled for this use. Note Valor is not labeled for winter barley.

Sharpen has a short-period of residual control and fairly narrow spectrum of control.

Finesse has a fairly broad spectrum of control.
● Needs rainfall to activate it
● There are populations of common chickweed and Italian ryegrass that are resistant to it
● Will carryover to vegetables and requires STS-soybeans to be planted after small grain harvest.

Valor has a broad spectrum of control for wheat.
● It does not have the rotational restrictions of Finesse
● Label states wheat needs to be planted at least one-inch deep
● Label requires it needs to apply at least 7-days ahead of no-till planting. In our trials, the interval should be at least 14-days. But in the current situation where it will be 3 to 4 weeks before planting, there is much higher level of crop safety.
● If you are considering conventional tillage, Valor has a 30-day before wheat planting
● Vertical tillage will disrupt the Valor herbicide layer and will reduce weed control.

Print Friendly, PDF & Email