Rangeland drought resilience study

by Megan Van Emon, MSU Extension Beef Cattle Specialist

Although the majority of the state has had ample rain this year, it’s good to be prepared when a drought does occur.  Drought preparedness is especially crucial when multi-year droughts occur.  I am currently working with several scientists on a drought resilience study: Identifying mechanisms of rangeland drought resilience: management strategies for sustainable ecosystem health.

Key Personnel

  • Sally Koerner, Assistant Professor, University of North Carolina – Greensboro
  • Lauren Porensky, Ecologist, USDA-ARS Rangeland Resources & Systems Research, Fort Collins, CO
  • Kevin Wilcox, Ecologist, USDA-ARS Rangeland Resources & Systems Research, Fort Collins, CO
  • Kim La Pierre, Senior Scientist, Smithsonian Environmental Research Center
  • Kurt Reinhart, Ecologist, USDA-ARS Range, and Livestock Research, Miles City, MT
  • Megan Van Emon, Extension Beef Cattle Specialist/Assistant Professor, Montana State University


Long-Term Goals

  1. Examine the resilience of rangeland function under various magnitudes of drought
  2. Assess the impacts of realistic grazing strategies on long-term sustainability and resilience of rangeland function, both during and after extreme droughts
  3. Provide relevant information and tools to land managers to optimize management strategies focused on long-term forage quantity and quality after extreme droughts


Supporting Objectives

  1. Identify drought-driven “tipping points”, where forage quantity and quality suffer disproportionately large declines
  2. Quantify drought impacts on plant community structure and soil properties
  3. Explore the direct and indirect mechanisms controlling forage quality and quantity responses to drought
  4. Assess rancher philosophies concerning grazing during and after multi-year droughts
  5. Examine how realistic grazing strategies during/after drought effect plant community structure, soil abiotic and biotic properties, and forage quality and quantity
  6. Promote stakeholder implementation of research findings through producer-based meetings, extension bulletins, local field days, and non-traditional web-based learning as well as the development of an online management tool


Research Sites

  1. Fort Keogh Livestock and Range Research Laboratory, Miles City, MT
  2. Thunder Basin National Grassland, Northeastern WY


Key Activities

  • Drought manipulation – Assess ecosystem response to differing drought intensities
    • Rainfall reduction gradient – 5 levels
      • Open for discussion
    • Rainfall reduction will be based on the current year’s precipitation
    • Rainout shelters will be in place from April to September
    • Measure impact of a reduction of spring moisture on mixed-grass prairie ecosystem
  • Grazing manipulation – Evaluate differing grazing rest rotations during drought on the ecosystem
    • Grazing rotations – 3 levels – We want your input
      • Example: graze annually (control), do not graze in year two of drought, do not graze in year one of recovery
    • Graze to moderate level
      • Open for discussion
    • Timing of grazing
      • Open for discussion
    • Field sampling – pre-drought, during drought, and during recovery
      • Forage quality and quantity
      • Soil abiotic factors
      • Soil microbial makeup
      • Plant species makeup
    • Management response to drought assessment
      • Assess rancher grazing strategies during and after a multi-year drought
      • Evaluate drought management tools used, drought management strategies, production information, preparedness for multi-year drought
      • Field days and meetings at each research site for demonstrations and assessment of the project
    • Stakeholder implementation of research findings
      • Provide research findings to develop new and update existing grazing strategies during multi-year droughts
      • Conduct producer-based meetings to evaluate project progress and discuss current results
      • Develop a web-based tool for aiding in drought management strategy development


Several factors will be determined based on survey feedback, including the rainfall reduction gradient, grazing intensity, and timing of grazing.  We are asking for Montana and Wyoming beef cattle producers to complete the Rangeland Drought Resilience Survey. The survey information includes how grazing and cattle management strategies were altered during drought, how management strategies may be altered in a single or multi-year drought, and feedback on the study design to determine the impacts of drought severity and length on rangeland response.



Researchers seek information from Montana cattle producers and veterinarians

5L Ranch red angus calf warm in strawResearchers from Montana State University Extension and Washington State University are asking Montana beef cattle producers and veterinarians to participate in a voluntary online survey to learn more about a novel form of neonatal calf pneumonia found in Montana.

Rachel Endecott, MSU Extension beef specialist, and colleagues at WSU said that a unique form of neonatal calf pneumonia has been diagnosed in several Montana beef herds over the last 6-8 years. The majority of affected calves are relatively normal at birth, but go on to develop signs of pneumonia within the first 1-4 days of life and die due to respiratory failure, Endecott said. A small proportion of calves with this problem are born dead, she added.

Samples from these animals have been submitted to veterinary diagnostic laboratories where they were diagnosed with pneumonia, but a specific cause was not identified, according to Endecott. Researchers believe that affected herds typically experience a three to five percent (or greater) increase in calf losses associated with this problem the first year it is recognized, and 0.5-1.0 percent greater calf losses in subsequent calving years. Endecott said more information is needed to better understand the problem.

MSU Extension and WSU researchers will use the data collected through these surveys to help investigate the prevalence of this unique form of neonatal calf pneumonia in Montana and better estimate its impact on producers, Endecott said. The survey results will then be used to help guide a study to determine the cause of the disease and develop a treatment and/or management strategy to prevent calf losses.

Endecott noted the survey should take only a couple of minutes.

“We appreciate the involvement of all beef cattle producers and veterinarians in helping us better understand this illness so that we can manage it appropriately,” Endecott said.

The surveys can be found online at

Contact: Rachel Endecott, (406) 994-3747 or

Fire Effects in the Northern Great Plains

Heat Duration In MinutesInformation provided by Dr. Mark Petersen of the Fort Keogh Livestock and Range Research Laboratory in Miles City.

Fire and grazing are natural and important processes in maintaining grasslands in the Great Plains and elsewhere.  Active fire suppression has in fact been recognized as a key disruptive force in rangeland ecosystem integrity throughout the world.  Fire’s ecological effects are numerous and complex.  Fire can manipulate nutrient dynamics, soils, vegetation, and animals.

Primary factors affecting community response are timing, frequency, and intensity of fire relative to the biology of organisms examined.  Fire effects on total plant productivity in the northern Great Plains are neutral to positive.  Native perennial grass productivity generally increases following fire.  Neutral responses in total productivity occur when increases in native perennial grasses are offset by reductions in annual grasses and forbs, which are predominantly non-native and non-preferred species.  Fire causes an immediate reduction of standing dead material and litter.  The combustion of standing dead material is a loss of forage in the near term.  The reduction in litter can alter light and moisture relations at the soil surface, promoting increased productivity and discouraging establishment of non-native species.  Reduction of standing dead material and litter as well as improved forage quality of new growth also attract grazers to burned sites.

Fire Season Effect on Brome Density
Response to fire can be species-specific, allowing targeted control of native weeds, such as purple threeawn, pricklypear cactus and juniper.  Invasive non-native weeds, such as annual bromes are also susceptible to selective control with fire and fire can kill seeds of some noxious invasive species.

Fire has even been shown to selectively control pest grasshopper species.   As an evolutionary process, fire cannot be substituted with any other management option.

Fire Effects on Weed Seed EmergenceThe dominant perennial grasses in the northern Great Plains are resistant to fire.  Western wheatgrass, threadleaf sedge, needle-and-thread, and blue grama were exposed to fires with a wide range of fuel loads (up to 8020 lb/ac) and hot, dry weather to determine the probability of fire-induced mortality.  No western wheatgrass or threadleaf sedge died.  To reach a 0.5 probability of mortality for needle-and-thread and blue grama, surface temperatures  exceeding lethal limits had to last 10.5 and 7.5 minutes, which required more than 7100 lb/ac of fuel.  Most combustion in grassland fuels is completed in 30 seconds to 2.5 minutes and fuel loads in the northern Great Plains are typically 600-2700 lb/ac.

Species such as Japanese brome can be reduced by fire through direct mortality of exposed plants and seeds, and indirect reduction through alterations in the microenvironment that reduce successful germination and establishment.  Established perennial weeds with protected buds, such as leafy spurge, are not harmed by fire, but seeds near the soil surface, in the litter, or in the canopy can be quite vulnerable to fire-induced mortality.

Heat Effects on EggsAs with plant species, animals are directly and indirectly affected by fire.  For example, ticks and grasshoppers that are in the plant litter or canopy  experience direct mortality from fire.

Additionally, we have shown some of the primary pest grasshopper species can be selectively controlled with fire.  Migratory grasshoppers show little egg mortality because they lay eggs deeply in the soil, whereas white-whiskered grasshoppers lay their eggs near the soil surface and commonly show 86% mortality.

Fire Ecology References available upon request. Email

MSGA’s Research, Education, and Endowment Foundation

Dusty Hahn, chairman of the Montana Stockgrowers Association’s Research, Education, and Endowment Foundation (REEF), explains what the foundation is and why it’s an important entity to help educate young people about the beef industry. For more information about REEF and to find out ways to support the foundation, please contact MSGA at (406) 442-3420 or visit us online: This video is brought to you by MSGA’s REEF.