As September rolls in, cattle producers’ attention will soon move toward making sure that they have sufficient feed stuffs for winter feeding. This is also the time that most producers decide on the use of and implementation of winter annuals. The use of winter annuals is very popular in the Southeast because of mild winter weather and adequate moisture for winter grazing. It is also very popular in low hay years as a way to stretch available forages to make it through the winter until the grass greens up again in the fall. While discussing the use of winter annuals may not seem to be related to nutrition, this year, with a reduced hay crop, adequate stands of winter annuals will be very important in meeting the nutritional needs of your cattle.
The first consideration is the type of annual you want to plant. Most producers decide between ryegrass, wheat, oats or rye along with a clover for nitrogen uptake and protein quality. Ryegrass continues to be the most popular of winter annuals. Ryegrass can be drilled, broadcast or incorporated into a prepared seedbed. Ryegrass will provide grazing in late fall through winter and into mid-spring. Ryegrass is mostly used by cattle producers who want to turn cows out in early spring on lush green grass. It will not only provide early grazing, but will afford the opportunity to feed hay early and reduce hay demands in the late winter and early spring.
Another popular choice is the use of small grains such as wheat, oats and rye. Small grain seed will give earlier grazing, but the seed should be covered with one to two inches of soil. Therefore, it is best to use a grain drill when planting small grains.
When implementing winter annuals, it is also profitable to plant an annual legume, such as Crimson or Arrowleaf Clover. The use of clover will increase the overall quality of the forage, thus improving animal performance. Clover, when inoculated, will fix nitrogen making this important nutrient available to your winter annuals and reducing fertilizer cost. If the legume makes up 25 percent or more of the stand, it is possible no additional nitrogen will be needed.
Although most producers understand the benefits of these forages, they are useless if stand failure occurs. Let’s look at some steps to consider to help assure an adequate stand with quality forages.
One of the first considerations is the method of planting. If you’re planting into an established grass, you must make sure that the stubble of the summer grass is less than one inch. Excess stubble makes it difficult to drill or broadcast seeds and have proper soil contact. Also, excess stubble will reduce sunlight the new plants will need to thrive. Heavy grazing and clipping are the two most popular ways to reduce stubble. If planting into a prepared seedbed, make sure of the seeding depth and do not plant the seeds at a depth that is more than seven times greater than the diameter of the seed.
Another consideration is determining the best date for planting. While winter annuals are relatively easy to establish, there is still the fact that the weather in some years is more suitable for growing annuals than in other. While we cannot control the weather, we can control being prepared when the weather is best for planting. Have the needed seed, make sure the land is prepared and have your equipment in good working condition to be in the fields at the proper time. If a window of opportunity is missed, you could have a reduced stand with poor results. Also, planting too early may expose the seed to excessive heat and competition from established summer grasses, while planting too late in the fall may lead to winter kill. It is always good to be prepared for planting in mid- to late-September.
Another concern when preparing for planting winter annuals is the seeding rate. Know the recommended seeding rates of the crop you are trying to establish. If conditions are less than favorable, increase the seeding rate to help assure an adequate stand. It is better to seed at a heavier rate, if in the end you have a higher stocking rate.
Now that you have made the decision of what to plant and when to plant, the next consideration is to determine factors that could possibly affect the quality of the grass stand.
One of the first considerations is proper soil nutrients. It is always best to do a soil test and to fertilize according to the results. In a prepared seedbed, you should add fertilizer to the seedbed; while in drilled situations, you should fertilize after the emergence of the grass.
Another decision is to make sure to reduce insect pressure. I have seen problems with army worms in winter annuals. Remember you must always be on the lookout for insect pressure in young, tender grass no matter the time of year.
The last consideration when establishing and grazing winter forages is to make sure not to graze the stand early. One of the biggest detriments to a good stand is letting cows on the grass too early. Do not graze if the fields are soft and muddy; always make sure that you can not pull the plant up by the root before grazing. Once the plant has been pulled by the root the plant is done and will not continue to grow.
After establishing good winter forage, there are nutritionally related concerns that must be considered as well. One of the first concerns is realizing the high moisture content of the grass. Cattle grazing high moisture grass will have a tendency to have very loose stool, may maintain winter hair longer and may have a "washed out" look about them. The loose stool really speeds up passage rate of nutrients and the cattle may not perform as well as you would like on the grass. The addition of hay or other high roughage products will reduce the problems mentioned and the cattle will look better and perform at a higher level. Also, if you have the ability to graze the cattle for only a couple of hours a day, you will see less problems and the grass will last longer as well.
Another concern in winter grass, especially with the addition of clover, is bloat. If you are grazing winter annuals on a continuous basis, I would recommend a bloat block for at least 21 days before grazing begins. This will reduce any problems with bloat and help the cows be more efficient in utilizing the grass.
A final concern is grass tetney. Grass tetney is caused by a build up of potassium nitrate that binds to magnesium reducing the intake from the plant. This can be deadly in cows and is more prevalent on cool cloudy days when the grass is actively growing. To reduce grass tetney, a mineral that is at least 14 percent magnesium should be provided to your cows on a free choice basis at least 28 days prior to grazing winter forages.
Jimmy Hughes is AFC’s animal nutritionist.