Unless you've learned to predict the future, it's always better to be safe than sorry when it comes to droughts affecting TX land. It's not a matter of if another drought will occur, but when. The right decisions can prepare us for these rain shortages, though, and we addressed some of them in Part I of this series. Now, let's look at best practices that get us ready for the future:
Foraging and grazing management for upcoming droughts
It's always important to pay attention to plant nutrient requirements. Test the soil for adequate pH, apply the needed fertilizer and hope for rain, to enhance fertilizer uptake efficiency. Applying nitrogen fertilizer prior to times when conditions are optimum for forage growth, such as the beginning of the growing season, helps maximize its utilization. In periods of limited soil moisture, delaying fertilizer application until moisture is present or imminent can also increase efficiency. When rain falls, pastures should be well-fed and ready to grow. If not managed properly during drought recovery, invasive species will take over and be difficult to eliminate.
"Being mindful of plant nutrients requirements is key to maintaining pasture welfare and helping to defend against droughts."
Heavy grazing during droughts severely stresses plants. Even when rain is ample, excessive consumption reduces root mass and can make plants less efficient at utilizing nutrients and moisture in the soil. It may be necessary to remove livestock from pastures and use stored feed for some time. Those without adequate facilities may have to establish a sacrifice paddock for feeding. Using a rotation stocking management system allows flexibility for this. Animals can also be fed in alleyways and/or lanes. If feeding livestock in other locations, make sure water is always available. If destocking has occurred due to drought, consider maintaining herd size at that number. It's much more economical to harvest hay from excess forage during good times than it is to feed stored forage and supplement during a drought.
Sorghum and millet for the best possible foraging
Summer annual grasses should be considered as temporary solutions to summer forage needs. They can be expensive to produce, difficult to manage and can develop prussic acid or nitrate poisoning within livestock. Some desirable characteristics include rapid growth, excellent drought tolerance and good response to fertilizer and water. The most efficient and economical use of these grasses is in a management-intensive rotational grazing system. Summer annuals can be an excellent option in dry years.
Summer annual grasses that can be grown in Texas include sudangrass, forage sorghum, sorghum-sudangrass hybrids, pearl millet and crabgrass. These can be valuable in the development of a forage system. Each has unique growth characteristics that require proper management for optimum production.
Pearl millet is better adapted to sandy, acid soils than forage sorghum. It can be planted in spring by broadcasting or drilling at a soil depth of 1/2 to 1 inch. Pearl millet will regrow after harvest if a 5-inch stubble height is left. Be careful not to graze or mow pearl millet too closely because it can be killed. It will take about 4 to 6 weeks before it is ready for the next harvest. Grazing can continue until frost is expected. Pearl millet has a distinct advantage over the aforementioned alternatives because it doesn't produce prussic acid. However, millet can still cause nitrate poisoning just as sorghum can.
If you do need to use it, sorghum should be at least 30 inches tall and grazed to a stubble height of 5 to 7 inches. Forage sorghum is best used in a single hay cutting, when plants are in bloom or early dough stage. A mower-conditioner will be needed to crush the stems, which will decrease drying time.
Sudangrass is a rapid growing warm-season annual that can produce good quality forage. It has fine stems, and grows rapidly after grazing. Sudangrass plants usually yield lower compared with sorghum-sudangrass hybrids. Sorghum-sudangrass hybrids have the highest yield potential of all summer annuals, and can be used for grazing or silage. But like other annual sorghums, their forage is difficult to dry to moistures suitable for hay production. Sorghum-sudans should be rotationally grazed allowing regrowth height to reach 24 inches before grazing.
Other summer annuals for drought preparation
Crabgrass is commonly considered a weed, but possesses significant potential for supplying high-quality summer forage. It works best with well-drained soils such as sand, sandy-loam, loamy-fine sand, pure loam and silt loam, when utilized in a rotational grazing system.
Summer annuals need a good supply of nutrients for high yields. Lime, phosphorus and potassium should be applied according to soil-test recommendations. Nitrogen is important, and also should be added at a rate between 60 to 100 pounds per acre at green-up. If planning additional harvests, 40 to 60 pounds of nitrogen per acre may be added after each harvest. Warm season annuals do require annual land preparation, planting and fertilization, and thus may not be economical in light of high diesel, seed, fertilizer and irrigation prices. If summer precipitation limits or prevents hay production, winter annuals are the rancher's next best option.
Pre-drought management is undeniably complex, taking place throughout the calendar year. Be sure to have cattle graze properly in the summer and plan ahead for fall, winter and spring forage production, so that the feeding of expensive hay or supplements is minimized. Despite the current moisture shortage, adopting these practices should be a priority of any farmer buying property in Texas and setting up an operation in the Lone Star State.
Dr. Vanessa Corriher-Olson is Associate Professor and Forage Extension Specialist at the Texas A&M Agrilife Research and Extension Center.