Proper grazing management a way to avoid drought effects
By Dr. Dirk Philipp, Department of Animal Science, University of Arkansas—Fayetteville
For this month’s issue, there is certainly no topic more current to write about than the ongoing drought and what can be done to avoid negative drought effects in the future. Nobody can say if droughty years become the norm, or if this year is followed by some years of average or even above-average precipitation. Constant management adjustments to environmental conditions are always necessary in agriculture, and while the current drought appears to be an aberration, any farm improvements will help deal with below-normal precipitation periods even during average years. Grazing management is at the very top of elements needed for operating a livestock business successfully and for avoiding negative long-term effects of drought periods.
Forage growth varies from year to year largely depending on the precipitation patterns in terms of the annual average, but also in terms of distribution within the year. Therefore, it us useful to record forage production and carrying capacities along with rainfall data continuously over several years to determine optimal stocking rates which can then be adjusted according to the environmental conditions. An example from southern Texas indicates how a flexible, low-risk approach might look like: The ranch manager in this case maintains a cow herd at 40% of the long-term total carrying capacity while the remainder is balanced with stocker calves. During years with good forage production, more calves are used for grazing, while during years with less forage production, a lower number of calves will be utilized. This strategy has provided good control over forage management regardless of climatic fluctuations.
During drought periods, it is crucial to reduce grazing pressure, as overgrazing will stress plants further with the result of long-term damage to the sward. One strategy during those times may be to sacrifice pasture areas that are already slated for renovation while stocking rates should be reduced on usually productive and healthy pastures. While weeds can quickly become a problem, herbicide applications should be delayed until after the drought. During hot and dry weather, drought avoidance mechanisms in plants impede herbicide entry into leaf tissue, resulting in little actual weed control. Similarly, fertilizer should be applied once weather conditions improve and rain is in the forecast. In this context, continuously maintaining adequate soil fertility and controlling weeds will give an edge once drought sets in and will help pastures recover.
Grazing methods such as rotational stocking or strip grazing result in better forage utilization than, for example, continuous stocking. Unfortunately, many producers still shirk from improving their pasture management. Given the relatively small average beef farm size in Arkansas, fenced paddocks can be set up in a relatively short amount of time and cost-effectively. During a drought, forage can then be used more efficiently and cattle have less opportunity to patch- or spot-graze. An evenly grazed sward is less prone to bare soil that in turn will hold more moisture as soil compaction and surface exposure is reduced to a minimum. This will also help control weeds that can spread rapidly during drought due to decreased competition from desired plants.
Establishing paddocks for better forage management and utilization requires water access points that will enhance beef production efficiency as well. The provision of fresh high-quality water to livestock is crucial for getting animals through hot and dry weather. A mature animal requires around 40 gallons of water each day in hot weather. In a situation like the current one, cattle will be severely affected and even die if they do not have access to sufficient amounts of water on a regular basis. Calves are naturally more affected by high temperatures than mature cows. During the process of switching from a single-pasture grazing plan to one that entails several paddocks, shade structures may have to be established anew, or paddocks laid out in a way that would strategically include shaded areas such as tree rows. With respect to watering devices, tire tanks are becoming increasingly popular among producers due to their relatively simple and fail-proof design and low-cost construction.