Herbicide Use and Grazing Options

Herbicide Use May Restrict Grazing Options for Cover Crops

Interest in cover crops has dramatically increased  due to their many potential benefits. In addition to conservation purposes, cover crops can provide forage for livestock producers. It is important for  livestock producers to consider restrictions on labels  of herbicides used earlier in the growing season if they intend to use the cover crop as a forage source. The two primary reasons for label restrictions related to cover crops are:

  1. Herbicide residues may prevent  successful establishment of the cover crop
  2. Residue tolerances have not been established for the presence of the herbicide within the cover crop

Regardless of the reason  for the restriction, failing to follow the restrictions is a  violation of the label and therefore a punishable offense. The following tables list herbicide products that allow  the establishment of cover crops for the purpose of  grazing or forage harvest during the same cropping  season as application. Herbicides are divided into three categories based on the minimum interval between  application and planting of cover crops intended for  forage purposes. The first group of herbicides allows planting of the indicated cover crops within four months of application; the herbicide label will list the specific  time interval. The second group of products requires a minimum of four months between application and planting of cover crops, whereas a 4.5 month interval is required for the third group.
The intent of this bulletin  is to assist livestock producers in identifying herbicides that are compatible in cropping systems that use cover crops for forage. It is not intended to eliminate the need  to read the label and determine specific use restrictions. Due to the large number of generic and private brand products, not all products are included in these tables. Inclusion of a product in this bulletin does not imply  endorsement of that particular brand, nor does exclusion imply non-approval.


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