The Forgotten Forage: Corn Residue

Finally! In my area we have gotten enough rain to recharge the system and combined with the temperature drop, the fall flush of forage growth is in full swing.

I hope you are experiencing this flush of growth that I am seeing. For graziers, life is good again.

After this summer there seems to be one nagging question on a lot of producers’ minds. Will I have enough forage to make it through winter?

This question comes from the fact that many producers experienced reduced hay production and also fed hay to keep from destroying their perennial pastures.

Several graziers have gotten past the basic feed budgeting issue and are asking “What could I be doing now to ensure I will have enough feed for winter?”

Answers to this question include, planting winter annuals, making alfalfa hay after it is dormant, using drought-stressed corn silage, buying hay or limit feeding grain.

Corn residue. Yet one of the cheapest and most abundant fall feeds is overlooked. What about corn residue?

Ohio produces more than three million acres of corn each year. Most of those acres are harvested for grain. After grain harvest the rest of the plant is left in the field.

One acre of corn residue can supply enough forage to sustain a 1,000-pound beef cow or equivalent for 1 1/2 to 2 months.

Any quick calculation you do should lead to the conclusion that there is enough feed remaining on corn fields after harvest to significantly increase the grazing days for ruminant livestock.

The real economic advantage of using corn residue in a livestock operation is that the cost of producing the feed is paid for by the grain operation.

In contrast when using an annual forage crop for grazing, the cost of establishing and growing the feed needs to be paid for by the livestock operation.

Finding answers. Sounds good, but how would you go about grazing corn residue?

The easiest way for most operations would be to graze immediately after harvest for 30-60 days to take maximum advantage of the feed value of the residue.

It deteriorates over time. This would allow the permanent pastures to “stockpile” additional days of fall growth that could be grazed after the animals come off the corn fields.

You could graze corn fields all winter if you wanted but you would need to provide supplemental feed and select well-drained fields.

Livestock will selectively graze the most palatable portions of the residue first, starting with the grain, leaves, and husks and then the cobs and stalks.

Generally, animals will leave 75 percent to 80 percent of total residue in the field, especially if they are rotated to new areas before much of the cob and stalk material is consumed.

Limiting access by strip grazing will give you an increased stocking rate and greater utilization of the residue. This can be accomplished by using portable electric fencing.

Corn residue is a great fit if you have non-lactating, mature beef cows or ewes that are in the middle trimester of gestation and are in desirable body condition.

If corn is visible in the manure, supplementation with anything other than vitamins and minerals is probably not needed.

Several studies have shown that dry cows will at least maintain body weight and may gain up to 1 pound per head daily while grazing corn stalks that have grain, husk and leaves to select.

Field issues. Won’t this create problems with the crop fields?

With livestock leaving 75 percent to 80 percent of total residue in the field, conservation compliance should not be an issue.

But it never hurts to check with your local Natural Resource Conservation Service office to see if this would change your conservation plan.

Soil compaction is the biggest reason given why corn residue is not grazed. Livestock can cause soil compaction, but the compaction they cause is generally shallow.

Studies indicate that soil compaction from cows grazing corn residue is limited to the top 6 inches of soil.

Shallow compaction can be corrected by disc, chisel-plow or the freeze-thaw action of the soil.

The two main factors that change the severity of compaction were soil moisture and soil type. In each of those studies, no significant difference was found in the yield of the soybeans following the residue grazing, even using no-till.

Compaction could be minimized by grazing the residue immediately after harvest, removing the livestock after 60 days to allow the soil’s freeze-thaw action to break up surface compaction.

Producers should pay attention to the soil types of the crop fields and remove livestock when the fields are muddy.

Concern. Controlling livestock is another issue that concerns many crop producers.

Fencing around many crop fields has been removed for various reasons. Portable electric fencing that can be removed before field work begins is an attractive option.

The use of single strand electric fencing may be the least expensive method for controlling livestock, however, location should be taken into consideration when determining the type of fencing to be used. Liability is always a concern with pastured livestock.

So why not consider using corn residue to help extend tight forage supplies this winter?

(Jeff McCutcheon is an OSU Extension, Agriculture and Natural Resources Agent in Knox County.)