Protecting Plant Vigor During a Drought

Most producers have several types of forage plants in their pastures. One type of plant is the bunch-type perennial grasses and forbs. These plants are native and introduced species. Spring growth and regrowth after grazing comes from stored plant food in the root system of the plant. These plants are often weakened by a drought due to lack of growth and lack of stored plant food in the root system. As some growth occurs, these plants must be protected from close, continuous grazing or they will die. Loss of these bunch-type perennial plants will be injurious to future forage production and will take years to replenish, if ever. Another type of plant is perennial sod grasses. These plants regrow from stored plant food in the root system. They differ from bunch type plants in that they can better stand close, continuous grazing and abuse. It is therefore advised to use these pastures (bahia and bermudagrass) as sacrifice pastures (pastures where cows remain and are fed hay and supplemental feeds). This protects the native and improved bunch-type plants, and helps build up manure and nutrients to be used by the bermuda or bahia plants when rainfall does occur. Limit or flash grazing bunch-type plants, while maintaining relatively large stubble heights to protect them, is advised as greenup occurs after a rain.

Weeds should be controlled so they do not compete with grasses for available moisture. While they can be palatable when small, weeds quickly grow and become unpalatable. Others can be poisonous in nature. Poisonous weeds are usually not palatable mixed with other forage plants. They are eaten during times of drought because other forage is lacking or because the poisonous plants can become more palatable as they dry. It is important to identify what plants green up in the spring or after a rain to determine proper use and/or control. Manage so that water from limited rainfall is utilized by forage species, not weeds and brush.

In periods of limited hay production, it is important to produce high quality hay. Proper time to harvest hay will increase the nutrient content of the hay. Hay from other non-traditional sources can be used in times of drought. This includes crop residues, drought-out corn or sorghum, and peanut, rice and wheat stubble. Although the quality might be low, these hay sources can be supplemented to correct nutrient deficiencies, or treated to increase quality (ammoniation for example). Extension bulletins are available on ammoniation of hay, and other options.

Pastures should be grazed according to a plan to increase forage utilization. Producers cannot afford to lose limited forage to improper grazing practices (i.e. trampling, etc.) Temporary electric fencing can help increase forage consumed in grazing pastures and allow for specialized grazing techniques such as creep grazing, limited grazing or grazing based on animal requirements. The use of crop residues and other forages for grazing to give pastures extra rest and time to recover can help.

Harvested or bought hay in round bales needs to be protected from excess weathering. Baling good, tight, uniform bales, and storage that avoids contact with the ground will help prevent hay from deteriorating.

During drought conditions, it is important to test hays for nutrient content and possible feeding problems as nitrate poisoning or prussic acid poisoning. Forage analysis for nutrient content will assist a producer in buying the needed supplemental feeds. Forage should be tested for nitrate and prussic acid poisoning if either is suspected in the forage.