Pasture & Range: December 2000

We've had several twists of fate in the southern Oklahoma—north Texas region during October. Many people were delaying planting winter pasture because of low soil moisture and the small chance of rainfall. Others crossed their fingers and dusted pasture in. The rainfall shortage was remedied over much of this region in late October, when we received 4 to 9 inches within just a few weeks' time. Continued mild temperatures have allowed winter pasture forages to accelerate growth so that many producers will be able to turn cattle onto pasture close to the customary time.

Rainfall is a necessary commodity for any forage-based livestock operation; however, when we get too much moisture (did I really say that?), there are some potential problems. Trampling damage to winter pasture forage can severely impair a winter pasture stocker operation. The major impact is a reduction in forage production, but another problem worthy of noting is a potential decrease in average daily gain, which results from higher livestock energy requirements for cattle with mud on their lower body and sides. A low wind chill factor more adversely affects cattle in this condition.

Generally the root of the trampling damage problem starts with soil texture and planting technique. Sandy soils rarely sustain trampling damage, unless excessive growth and grazing management practices have allowed the forage to lodge. Sandy soils have good internal drainage and are not as susceptible to developing traffic pans. Loamy soils have a combination of soil particle sizes. When these soils are compacted under wet conditions, they can have poor internal and surface drainage, traffic pans, and the problems discussed above. Obviously, winter pasture planted on clay soils is also subject to these problems.

Trampling damage can be a problem from fall through spring, but normally the most detrimental effects are seen from late fall through winter. Sometimes cattle are turned out on pasture that is not ready to be grazed in the fall, resulting in many of the plants being pulled up by the roots or exhibiting a slower regrowth rate. Wait until forage is 6 to 8 inches tall and well rooted before allowing full-time grazing. This method will enable the grass to establish a better base that diminishes trampling damage later in the growing season.

Oftentimes, even if you have a well-developed stand before turning cattle onto pasture, you may still have trampling problems that planting techniques generally play a large role in. If you have loamy or clay-textured soils, some form of minimal tillage practice will help reduce the incidence of trampling problems. No-till, sod seeding, broadcast and treading in the seed with animal impact on a dormant or near-dormant forage base, and broadcast and light disking are planting methods that can minimize trampling effects on winter pastures. When tilled seedbeds are on loamy or clay-textured soils and receive high rainfall amounts and heavy livestock traffic, livestock often sink to the maximum tillage depth, from several inches to 1 foot, in some cases. If the cattle are sinking that low, you can imagine what happens to the forage that the cattle rely on for gain.

Limit- or top-grazing the pasture and shortening grazing rotations can reduce trampling damage. It's best to have an adjacent pasture such as dormant bermudagrass to move cattle to when conditions leading to trampling damage exist, such as standing water or snow and ice cover. Gates used for cattle access between pastures can also be a problem on winter pastures. I have worked with people in the southeastern United States who have lost calves because of having muddy lanes through gates and trying to drive cattle through too small an area. Allowing cattle to flow through gates while rotating through pastures can eliminate unnecessary losses and reduce trampling damage created by cattle running on boggy winter pasture. If you have a particularly wet-natured pasture, you can avoid a wreck if soil conditions are unfavorable by constructing an additional temporary gate adjacent to the gate you normally use.

Many pastures will have some trampling damage no matter what you do, which is just something that happens when a lot of cattle are grazing high-moisture cool-season forages. The key is realizing when the potential for trampling damage to winter pastures exists and then managing to keep it to a minimum.