June 12, 2009

After disaster strikes, replanting a grain crop may be nearly impossible due to herbicide carryover, the late planting date, or lack of seed. In some instances annual emergency forage crops might be your only choice. 

Before selecting any crop to replant as forage, check the label of previously applied herbicides. Many herbicides have restrictions and limitations on grazing or feeding forage grown in their presence. If you used anything other than glyphosate on the previous crop, there may be some injury.

Many herbicides for corn and milo will injure pearl millet, foxtail millet, and teff. Sudangrass, forage sorghum, and sorghum-sudan hybrids will tolerate moderate levels of atrazine. If Dual or Bicep-like herbicides had been applied, use safened seed for the replanted crop. These sorghums also tolerate most herbicides labeled for use with grain sorghum. Another possible emergency forage crop is short-season corn as silage or even drilling bin-run corn for late season pasture or hay, especially if corn herbicides eliminate other possibilities.

Soybean herbicides other than glyphosate cause even bigger problems for replanting to forages. All summer grasses are sensitive to most soybean herbicides. Sunflowers for silage and soybeans for hay or silage are among the few alternatives compatible with soybean herbicide carryover.

Nobody likes to replant, but if you must, select a forage that is compatible with your herbicides and your livestock.

Bruce Anderson
Extension Forage Specialist