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Manage drought, don’t let it manage you

Jack Arterburn for Progressive Cattleman Published on 24 May 2018
Drought with cattle

Although drought can negatively impact rangeland production, being prepared can reduce the devastation of drought this year and prevent impacts in the following years.

Develop an effective grazing system

Planning for a natural disaster, such as drought, is an essential part of a grazing plan for rangelands and an overall ranch management plan. A grazing plan lays out step-by-step management actions to utilize and improve the most expensive input, the feed resource. Proper grazing management is essential to prepare for drought and to manage rangeland through drought.

Rotational grazing is at the core of a proper grazing system, whether it is a simple or management-intensive system. Rotating through pastures during the growing season to avoid grazing the same pasture during the same season in consecutive years provides an opportunity for key species to recover after grazing.

Long recovery periods improve the ability for vegetation to absorb events, such as drought, by increasing root mass, nutrient stores and overall plant vigor, resulting in less short- and long-term detrimental effects.

Periodically providing an entire growing season of rest to grass by deferring grazing until after a hard freeze substantially improves plant resiliency, minimizing the impact of stressors, such as grazing, drought or fire. Stockpiled forage can be utilized as winter feed when grazing has minimal impact to dormant perennial grasses.

Know your forage resource

Monitoring forage resources annually not only allows you to track changes caused by environmental conditions or management actions but also provides an in-depth knowledge of your resources, allowing you to more effectively manage and plan.

Grass species have critical growth time periods, varying by species, when precipitation is important. Stress, such as grazing or drought, during these growth periods can be detrimental to plant health and vigor. For example, soil moisture on April 1 supports initial cool-season growth and the majority of growth is produced during May. Warm-season species generally initiate growth in May and begin rapidly growing in late June and July.

Forage growth will be significantly impacted if soil moisture is not present during these time periods. Precipitation after the critical window does little to contribute to forage growth. If grazing to grass occurs in subsequent years during this growth window, plant health, vigor and production will be reduced.

Establish (and follow) trigger dates

Critical growth periods also act as dates that trigger specific management actions if adequate moisture conditions are not present. Soil moisture conditions often set the trend for forage growth, emphasizing the importance of monitoring root zone soil moisture on the ranch.

There is an online soil moisture monitoring tool which can give an indication of soil moisture conditions for your region (NASA Grace-based shallow groundwater drought indicator). Evaluate trigger dates and needed decisions based on current conditions (United States drought monitor) compared to long-term averages (High Plains Regional Climate Center CLIMOD) as well as forecasts (NOAA Climate prediction center).

The importance of residual

The importance of plant residual, the plant growth remaining following the grazing season, is an often overlooked component to plant health. Not leaving enough residual by staying in a pasture too long or taking too much off is extremely detrimental to forage production in the following year or years to come.

A minimum amount of plant residue by weight is required each year to protect the soil surface, maintain the health of plant community and increase rainfall absorption into the soil. The amount of residue required will vary between plant communities and soil types but will not vary between years.

Each year, whether above or below average production, pastures should have the same minimum amount of residue. In drought years, this is especially difficult but even more critical in order to reduce long-term reductions in forage growth and to increase absorption of precipitation.

The adage of “take half, leave half” may be appropriate during an average year – but not during drought. Reduction of forage growth during drought does not equate to the same reduction in stocking rate. The residual forage needed to maintain the long-term vigor of the plant community remains constant.

Failing to leave enough residual forage, especially during drought, can have long-term detrimental impacts to plant health and vigor. As a result, reducing stocking rate reduction is necessary during drought.

Reducing stocking rate

The stocking rate is the animal demand over a period of time. Therefore, reducing the grazing pressure can be accomplished by reducing animal demand, reducing the grazing period or a combination of both. Grazing period length is reduced by rotating through pastures faster. Animal demand can be reduced by early weaning and culling.

Research has shown the financial advantage of getting ahead of the curve by using trigger dates to marketing animals before a drought becomes severe. Production records help with identifying underperforming animals, making culling decisions easy. It is important to understand the consequences of culling, such as tax implications and impacts on future cash flow.

Reducing stocking rate doesn’t automatically mean cattle need to be sold. At times, there are creative and economical ways to reduce animal demand by removing cattle from the pastures and feeding. In some locations, the use of low-quality roughage fed with an energy-dense byproduct, such as distillers grains, can be an economical alternative feed source.

Beware of feeding a protein source, such as distillers grains, on pasture during drought conditions. Protein supplementation can actually increase intake of grazed forages, leading to overgrazing if additional roughage is not also included.

Plan, implement, evaluate

Whether planning for, experiencing or recovering from a drought, having a plan can reduce risk, stress, as well as short- and long-term impacts. Develop a well-defined, yet flexible plan for how to capture the most value from your forage resources while also providing for long-term range health.

Monitor moisture conditions before and during the growing season and be disciplined to follow established trigger dates for management actions if precipitation levels are not met. A step-by-step plan in writing can help make executing difficult management decisions easier.

Each winter, especially following a drought, evaluate the previous year’s growing conditions and residual forage residue as well as current soil moisture conditions. Use this information to evaluate and estimate how forage available will meet stocking demands prior to spring green-up.

Low residual forage and low soil moisture going into the winter does not set pastures up well for the next growing season. University extension and the Natural Resource Conservation Service have resources and tools that can be helpful in building and executing a drought management plan. One example is Drought information and resources.   end mark

ILLUSTRATION: Illustration by Carrie Stockebrand.

Jack Arterburn
  • Jack Arterburn

  • Beef Systems Extension Educator
  • University of Nebraska
  • Email Jack Arterburn