Straight From the Horse's Mouth

Duane A. Lienemann, UNL Extension Educator, Webster County November 1, 2009 Edition I have received several queries about the possibility of grazing winter wheat this fall since it is taking so long to get corn and grain sorghum out of the field. Let’s take a look at some considerations in making this determination. Producers who want wheat for pasture for their livestock this fall will have to make some decisions that could affect both the forage production and ultimate grain yield potential of the wheat.

First, and this may be a problem, wheat intended for pasture should have been seeded at a higher rate. It has been found that the best grazing occurs in wheat that was planted at about 120 pounds of seed per acre and planted early. Wheat for pasture has to be planted earlier than the optimal dates for grain-only production, about two to three weeks before the Hessian-fly free date. That however makes the wheat planted for pasture more susceptible to damage from Hessian flies, early-season armyworms and flea beetles, and wheat streak mosaic, so most people don’t consider that when they plan wheat planting. Still, unless fall is unusually warm late into the season, forage production simply won't be sufficient for pasturing cattle if it's not planted early. So a producer will have to walk out across the field he is considering grazing and make some observations.

The first thing that must be considered is that cattle should not go onto wheat pasture until the crown roots have developed enough to anchor the plants. Don't just look at top growth and assume that if the wheat is growing good that crown roots have developed. Sometimes that's not the case. Actually check some plants to make sure there is good root development. The general rule is, wheat should have about 6-12 inches of top growth before pasturing the crop. But, the true test of wheat readiness is crown roots that have developed enough that cattle will find it hard to pull plants out of the ground as they graze.

Another important consideration is that often the high crude protein and low fiber contents in wheat pasture are associated with bloat. Cool, moist conditions also favor bloating. To aid in preventing bloat, it is imperative that you don’t put hungry cattle on lush pasture. Get them full with dry hay before putting them out into the lush wheat. When grazing begins, carefully monitor to identify animals more susceptible to bloat, so they can be removed before chance of loss. Observing the cattle often to detect bloat can prevent loss. Bloat potential is greatest during the 3- to 4-week periods of lush growth in the fall and again in early spring. Feeding Bloat-Guard (poloxalene) as a dry or liquid energy supplement, molasses block, or mineral supplement is the most effective procedure to prevent bloat. Feeding high-quality grass hay, silage or grain with Rumensin or Bovatec will also minimize bloat potential.

Any time you put cattle in lush green growth you need to guard against Grass Tetany which is characterized by a low blood magnesium level in livestock. It occurs more often in older cows nursing young calves, but may affect stockers as well if a producer is looking at retained ownership of his weaned calves. Tetany mostly however occurs more frequently during rapid spring growth following cool temperatures (45 to 60 degrees F), but may occur in fall. The easiest prevention is to provide 6 to 8 percent magnesium in a palatable, free-choice mineral supplement. While it is needed, along with added calcium, for late pregnant and early lactating cows grazing wheat forage, it is not needed for stockers. Contrary to popular belief, magnesium plays no known role in reducing bloat on wheat. This belief undoubtedly was started when magnesium tetany, which is a serious problem with cows, was believed to be the cause of sudden death syndrome among calves. This is not the case.

Producers should plan to use extra nitrogen on wheat that's pastured. Cattle remove N that's in the wheat forage. So, seeing N deficiencies in the crop after the cattle have moved elsewhere is fairly common. To maintain grain yields, producers should apply another 40 pounds of N per acre for every 100 pounds of animal gain per acre, he advised. A good approach for this is a split application, with part of the N going on in early fall and part being applied as soon as the cattle are pulled off in late winter or early spring.

If a producer does decide to utilize the wheat growth to stretch forage until he can get to stalks with his cows he needs to make sure that he can provide a dry area available to move the cattle onto when the fields get wet. With the recent weather we have been having. That will help limit soil compaction problems, which can be a factor if keeping cattle on wet wheat fields.

Texas, Oklahoma and Kansas producers have been utilizing wheat pastures for many years. Our neighbors to the south may have it right. It could be a good relief for lacking forages because of drought conditions leading up to late harvest and a lack of typical stalk grazing to stretch the old forage dollar. Just take note of those things that need to be considered before jumping into fall grazing of winter wheat. The preceding information comes from the research and personal observations of the writer which may or may not reflect the views of UNL or UNL Extension. For more further information on these or other topics contact D. A. Lienemann, UNL Extension Educator for Webster County in Red Cloud, (402) 746-3417 or email to: dlienemann2@unl.edu