Extension Education: Drought Impacts Grazing Practices

Producers are understandably sensitive about a drought this coming grazing season. Drought is likely, but clearly not a certainty. 

There is also little evidence to support one year’s drought having much impact on the following year’s productivity.

Long-range forecasts are not encouraging. However, assessing precipitation received March through May can determine any potential for and severity of drought.

For our range clients and those using BLM lands, March, April and May are precipitation months that determine forage yields. The later precipitation comes, the less effect it will have on cool-season vegetation forage production; thus, if March and April are warm and dry, plants would have started to mature and would be less responsive to May precipitation. 

Elevation and location play important roles. When temperatures rise, soil thaws, growth starts and precipitation will have an effect. Areas farther east in Wyoming may have ecotypes and species that respond better to later season precipitation. 

The additional moisture that comes after growth starts varies, has a proportionally larger effect than in winter, and is the major reason one is better able to predict the grazing season forage yields from spring precipitation. 

Farther west, winter precipitation is greater and thus more important to forage yields than east of the continental divide.

Many federal land managers and producers, looking at the prospect of drought, are considering delayed turnout, destocking or reduced numbers, or early removal from pastures or allotments. Delayed turnout will be the least-effective option. In spring, cattle use much greater and differing areas than later because of water availability, water needs, and different plant phenology. Delayed turnout would put the livestock on areas they would ordinarily use later anyway. Grazing before seed stalk elongation has no impact on plant productivity. Delayed turnout also provides producers little time for finding alternative forages or making marketing decisions after a drought is evident.

If the producer’s operation is dependent upon spring precipitation for the year’s forage supply, early destocking may be the best solution and consequently grazing fewer animals on federal grazing permits. Agencies and producers should plan to monitor residual forage or percent utilization so animals can be removed early enough to leave adequate soil protection. Establish residual forage or use targets and monitoring locations early in the season. Many areas have sufficient forage to supply animals if there is water available. Grazing value may be sufficient to warrant hauling water to unwatered areas. 

I recommend permittees be prepared to go with reduced numbers, plenty of water hauling and be ready for an early off, based on monitored forage use levels. There is little reason for late turnout because early-season grazing is on a largely different group of species and habitats than later in the season. 

Michael Smith is a University of Wyoming Extension range management specialist and a professor in the Department of Ecosystem Science and Management in the College of Agriculture and Natural Resources. He can be reached at 307-766-2337 or at pearl@uwyo.edu.