Soil Fertility Management After Drought
Producers should exercise caution when restocking pasture and range damaged by the 2011 drought. Many perennial forage plants were forced into summer dormancy for survival due to the severity of the drought. During this period, dormant plants survived on energy reserves stored in plant crowns and roots when normally they would have generated energy through photosynthesis in green leaves. When favorable conditions returned in fall 2011, warm-season plants had little time to replenish stored energy reserves before winter dormancy.
To make matters worse, growing conditions throughout the winter were ideal for cool-season annual grass and early weed growth. Cool-season grasses have been a welcome source of forage production, but strong spring growth of grasses and weeds can delay warm-season grass growth and further weaken stands. Another possible complication is poor grazing management practices prior to the drought. If resources were pushed to the limit prior to the drought, then negative effects were magnified. Combined, these challenges have created a scenario in which warm-season perennial forage plants that account for the bulk of yearly production are entering the growing season in a weakened condition.
The bright side is that perennial forages are resilient if given the opportunity to recover through good grazing management. Grazing management is improved by rotational grazing, which allows control of stocking rate, where livestock graze, length of the grazing activity, and frequency and intensity of grazing. Control of each of these elements is critical for pasture and range recovery following drought.
In native range, providing rest to the range is an extremely important management activity. In extreme cases, such as instances where the crowns of plants have been grazed off, complete rest from grazing for an entire year may be required. However, this may not be a practical option for many producers. In that case, the next best option is doubling the land area requirement for running a cow for a year and deferring grazing through the growing season. Where good grazing management has been previously practiced, recovery will be good, but caution should still be the rule. Providing as much rest as possible during the growing season and reducing the normal stocking rate by 25 percent would further aid recovery.
Bermudagrass pastures have been hurt by the drought as well, but the rate of their recovery will be faster than with native grasses. The speed of recovery can be further enhanced by weed control and applying proper fertilizer based on soil test reports. If moisture conditions improve throughout 2012 and with proper fertilization, stocking rates within 10 to 20 percent of normal can be achieved.
In 1956, Vernon A. Young published a paper in the Journal of Range Management summarizing recovery following the 1949-54 drought. His words from 1956 have application now: "The damage resulting on the ranges of Texas from the 5-year drought period, 1949-54, can be correlated with land management and the type of soil. In general, ranges that were properly managed before and during the drought came through in fair to good condition; overstocked ranges were severely damaged and subsequent recovery has been very limited. Thus, ranchmen have evidence of the need for carrying out proper management practices year after year, not only to meet drought periods, but to build for an economic unit by capitalizing on the years of favorable moisture. Thus, the old rule still prevails that close grazing does not pay."
Young, V.A., 1956. The effect of the 1949-1954 drought on the ranges of Texas. J. Range Mgt. Vol. 9, pp. 139-142.