Late summer rains in western Kansas have improved attitudes and have helped green up many pastures. However, the drought and impacts of drought in that region are far from over.
Most counties in western Kansas have experienced 2 to 3 years of drought. The western third of the state still has averaged less than 75% of normal precipitation for the year. Drought conditions are expected to persist or intensify in western Kansas for the August 15 to November 30, 2013 time period.
Drought the last couple of years has not only reduced forage production but has also caused changes in plant composition. Cover of blue grama and buffalograss has declined. Taller grasses may have nearly disappeared. Meanwhile, cool-season annual grasses such as Japanese and downy brome may have appeared with fall and/or early spring moisture. Broadleaf weeds like western ragweed and heath aster may have survived because of deeper root systems than the grasses. Poisonous plants like snow-on-the-mountain and woolly loco may be more prevalent. As the shortgrass sod thins, mother nature fills in the gaps with other plants, especially annuals, when rainfall returns. Stolons allow buffalograss to recover from drought more quickly than blue grama.
Stocking rate is the primary range management principle that impacts plant and animal response. As stocking rates increase individual animal gains decline and gains/acre increase. Reduced forage production associated with drought may require a reduction in stocking rate. Complete destocking may be necessary if plant growth ceases. Ranchers can decrease pressure on grazing lands by culling more animals, improving grazing distribution, and weaning calves earlier.
What does rain in July and August do for forage production on western Kansas pastures? Other than regrowth from “grazing lawns” most of the forage production potential has occurred by mid-July. Late summer rains will often cause the grasses to produce seed heads with minimal leaf growth. Annual forbs will germinate.
Weed control may not be beneficial from an economic standpoint. Dense stands of western ragweed may reduce short grass production because of shading, but many forbs are deeper rooted than the grasses and cause minimal competition. Attempts at weed control during drought may not be very successful because of poor herbicide absorption. Treating poisonous plants generally enhances their palatability and increases consumption, which can be dangerous.
If at all possible, try to avoid heavy use of native rangelands in late summer. Rest during these months is critical for warm-season grasses to store carbohydrate reserves, and is important for winter survival and initiation of spring growth.
Monitor pastures for forage production. Adjust stocking rates as needed to maintain plant health and vigor. Reduce livestock numbers rather than feeding harvested forages. Use good grazing management during and after drought. Stay flexible and have a written plan of action.
Walt Fick, Range Management Specialist
whfick@ksu.edu
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