It’s Really Dry. Now What?

 

Conditions reported on June 28 for the U.S. Drought Monitor indicated deepening drought conditions in Western and Northeastern South Dakota. Statewide, during the most recent week, the area unaffected by dry conditions decreased from 53% to 39% and the area in moderate drought increased from 16% to 33%.

 

Management of pasture and rangeland to provide livestock feed always involves a balance of supply with demand. Uncertain moisture makes anticipation of vegetation supply difficult. Drought further complicates the balancing act, but demands a decisive response. Delaying a response or avoiding decisions never solves the issue. Balance must be maintained by reducing demand, increasing supply, or both.

 

 

 

Cows need significant nutrients to meet the requirements of lactation. Weaning calves eliminates the lactation requirement and substantially reduces forage consumed to meet the nutrient requirements of the cow. Additionally, as calves grow, their consumption of grazed forage increases. Early-weaning calves and removing them from pastures will substantially reduce forage demand. Johnson et al. reported a 36% reduction in pasture forage utilization with dry cows whose calves had been weaned early vs. cow-calf pairs. Early weaned calves can perform well in the feedlot. Consider retaining ownership and custom feeding to avoid the discount associated with selling lightweight, early-weaned calves.

 

 

This requires pregnancy diagnosis with ultrasound. It is key that cows diagnosed as open are immediately culled and marketed to eliminate their forage demand. This practice selects the most fertile cows that get pregnant early in the breeding season, ensuring that the remaining cattle are the most productive. While the overall herd size may need to be reduced, this practice ensures that the impact on overall productivity is minimized by improving herd reproductive performance. Additionally, the culled cows will be marketed earlier than most, avoiding the market downturn that is typical when herds are being downsized in a drought-stricken region.

 

 

A drought management plan should have trigger dates when a set percentage of cows should be sold based on a measure of drought severity, possibly a specific deficit in precipitation. The plan should call for a series of small cuts that start early in drought. A small percentage of the poorest performing cows culled early may be key to saving forage to reduce the magnitude of later cuts, thus retaining more cows in the long run. The plan should specify how to choose which cows to sell. If open cows have been identified for culling and additional reduction is necessary, comprehensive and up-to-date individual cow performance records can be invaluable to identifying the least productive cows. A computerized performance record program that can provide a ranked list of the cows that are least productive will support identifying the cows to sell. Selective culling can lessen the overall impact of herd reduction, much like culling the less fertile cows. Body condition scoring should also be employed to identify cows that are currently unthrifty. Demand could also be reduced by selling yearlings retained or purchased and carefully evaluating the bull inventory. Selling all the bulls may be a legitimate decision if it provides sufficient additional grazing.

 

 

 

A wide variety of alternative forages often become available during droughts. For example, CRP is often released for grazing or hay production, and cereal or corn grain crops that won’t produce adequate grain to harvest can be grazed or harvested as hay or silage. Additionally, cropland can be planted to cool-season or summer annual crops for the purpose of providing emergency forage during drought. If hayfield production is depressed and haying is not justifiable, these fields might be grazed if water is available or could be hauled. Additionally, if these hayfields are not fenced, temporary fence could be installed. Cover crops planted on idle cropland or following a grain crop might be an additional source of feed. All of these forage sources can have management concerns. These concerns include inadequate or unbalanced nutrient content, toxins such as nitrates and prussic acid, and grazing restrictions because of pesticide application. Awareness can allow for management of these concerns.