Source: AGRICULTURAL RESEARCH SERVICE submitted to
LOW RISK MANAGEMENT STRATEGIES FOR SUSTAINING RANGE BEEF CATTLE PRODUCTION SYSTEMS
Sponsoring Institution
Agricultural Research Service/USDA
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0406900
Grant No.
(N/A)
Project No.
5434-21630-001-00D
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Feb 21, 2003
Project End Date
Jan 30, 2008
Grant Year
(N/A)
Project Director
VERMEIRE L T
Recipient Organization
AGRICULTURAL RESEARCH SERVICE
(N/A)
MILES CITY,MT 59301
Performing Department
(N/A)
Non Technical Summary
(N/A)
Animal Health Component
50%
Research Effort Categories
Basic
50%
Applied
50%
Developmental
0%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
3021610107020%
1213310106030%
1020799101050%
Goals / Objectives
1. Quantify relative impacts of climatic variation and livestock grazing on sustainability of Northern Great Plains rangeland ecosystems and develop management strategies to ameliorate selected economic and ecological risks resulting from adverse impacts. a. Quantify impacts of spring drought and above average summer rainfall on primary productivity and proportion of plant species groups in the biomass. b. Quantify impacts of climatic conditions and varying livestock grazing tactics on primary productivity and plant species composition and diversity. c. Quantify impacts of grazing management strategies on soil C, CO2 flux, above- and below-ground biomass, and plant species composition. d. Quantify impacts of varying abiotic and biotic factors, particularly animal mediated impacts, on rate and extent of invasion and control of noxious weeds into rangeland dominated landscapes. e. Research and develop ecologically and economically sound rangeland restoration technologies for restoring degraded, weed infested rangeland ecosystems. 2. Quantify impacts of management tactics designed to improve the supply of quality forage in relation to nutritional needs of cattle on performance of grazing cattle and related economic indicators. a. Determine persistence and potential grazing value of experimental cultivars of seeded perennial forages on non-irrigated pastures for early spring or fall grazing, with emphasis on wheatgrasses and wildryes, b. Quantify impacts of varying seasons of calving (late winter, early spring, and late spring) on rangeland-based beef cattle production traits. c. Determine profit and associated annual risk as a function of season of calving and subsequent variations in post-weaning management strategies. 3. Evaluate in vitro gas production techniques to estimate seasonal variation in forage quality and predict performance in rangeland-based beef cow production systems.
Project Methods
Field-laboratory studies will evaluate how plants respond to grazing and environmental stress. Role of rangelands and management tactics in regulating atmospheric carbon dioxide flux will be assessed by measuring temporal changes in plant biomass, soil carbon and water, and carbon dioxide fluxes with chambers. Long-term impacts of environment on ecological condition will be assessed by evaluating changes in plant species composition inside and outside livestock exclosures and evaluating changes in herbage production and rooting dynamics with short-term droughts applied with a rain-out shelter. Fundamental life history, autecolgical studies will be initiated to quantify role that varying abiotic and biotic factors play in regulating the rate and extent of invasion and control of noxious weeds. Fundamental understandings of important ecological processes will be researched, developed, expanded, and ultimately incorporated into rangeland restoration technologies. The potential role of planted forages will be studied by monitoring herbage growth dynamics, cattle diets, & weight gains. Late winter, early spring, and late spring calving seasons will be evaluated for their effect on biologic and economic measures of rangeland beef production. In vitro gas production techniques will be used to evaluate seasonal variations in forage quality and results will be evaluated for their ability to accurately predict performance of grazing cattle.

Progress 02/21/03 to 01/30/08

Outputs
Progress Report Objectives (from AD-416) 1. Quantify relative impacts of climatic variation and livestock grazing on sustainability of Northern Great Plains rangeland ecosystems and develop management strategies to ameliorate selected economic and ecological risks resulting from adverse impacts. a. Quantify impacts of spring drought and above average summer rainfall on primary productivity and proportion of plant species groups in the biomass. b. Quantify impacts of climatic conditions and varying livestock grazing tactics on primary productivity and plant species composition and diversity. c. Quantify impacts of grazing management strategies on soil C, CO2 flux, above- and below-ground biomass, and plant species composition. d. Quantify impacts of varying abiotic and biotic factors, particularly animal mediated impacts, on rate and extent of invasion and control of noxious weeds into rangeland dominated landscapes. e. Research and develop ecologically and economically sound rangeland restoration technologies for restoring degraded, weed infested rangeland ecosystems. 2. Quantify impacts of management tactics designed to improve the supply of quality forage in relation to nutritional needs of cattle on performance of grazing cattle and related economic indicators. a. Determine persistence and potential grazing value of experimental cultivars of seeded perennial forages on non-irrigated pastures for early spring or fall grazing, with emphasis on wheatgrasses and wildryes, b. Quantify impacts of varying seasons of calving (late winter, early spring, and late spring) on rangeland-based beef cattle production traits. c. Determine profit and associated annual risk as a function of season of calving and subsequent variations in post-weaning management strategies. 3. Evaluate in vitro gas production techniques to estimate seasonal variation in forage quality and predict performance in rangeland-based beef cow production systems. Approach (from AD-416) Field-laboratory studies will evaluate how plants respond to grazing and environmental stress. Role of rangelands and management tactics in regulating atmospheric carbon dioxide flux will be assessed by measuring temporal changes in plant biomass, soil carbon and water, and carbon dioxide fluxes with chambers. Long-term impacts of environment on ecological condition will be assessed by evaluating changes in plant species composition inside and outside livestock exclosures and evaluating changes in herbage production and rooting dynamics with short- term droughts applied with a rain-out shelter. Fundamental life history, autecolgical studies will be initiated to quantify role that varying abiotic and biotic factors play in regulating the rate and extent of invasion and control of noxious weeds. Fundamental understandings of important ecological processes will be researched, developed, expanded, and ultimately incorporated into rangeland restoration technologies. The potential role of planted forages will be studied by monitoring herbage growth dynamics, cattle diets, & weight gains. Late winter, early spring, and late spring calving seasons will be evaluated for their effect on biologic and economic measures of rangeland beef production. In vitro gas production techniques will be used to evaluate seasonal variations in forage quality and results will be evaluated for their ability to accurately predict performance of grazing cattle. Significant Activities that Support Special Target Populations This final report documents research conducted under the in-house associated project CRIS 5434-21630-001-00D, Low Risk Management Strategies for Sustaining Range Beef Cattle Production Systems. Objectives addressed were 1) quantify relative impacts of climatic variation, livestock grazing, and fire on the sustainability of Northern Great Plains rangeland ecosystems and develop management strategies to ameliorate economic and ecological risks. Specifically, we quantified impacts of spring drought, above average summer and fall precipitation, grazing, and fire on herbage production, plant species composition and diversity, and rates of carbon sequestration; 2) quantify effectiveness of management tactics designed to enhance the supply of quality forage throughout the year and evaluated related economic indicators. Specifically, we evaluated persistence and potential grazing value of experimental cultivars of seeded perennial forages with emphasis on wheatgrasses and wildryes, quantified impacts of varying seasons of calving (late winter, early spring, and late spring) on rangeland-based beef cattle production traits, and determined profit and associated annual risk as a function of season of calving and subsequent variations in post-weaning management strategies; 3) evaluate in vitro gas production techniques to improve accuracy of forage quality estimates and prediction of animal performance in rangeland-based livestock production systems; and 4) identify fundamental factors affecting ingress of invasive weeds, particularly leafy spurge, into rangeland ecosystems and quantifying the modifying effects of livestock grazing on these processes and potential use of livestock grazing as a management tool. Research was aligned with the following components of the NP 205 Action Plan and addressed the stated problem areas: Component 1, Problem areas, Ecological Processes (objective 1), Ecological and economical sustainability (objective 1), and Decision support (objectives 1 and 2); Component 2, Problem areas, Improving forages for livestock production (objective 2)and Overcoming limitations to plant growth and development (objective 2); Component 3, Problem area, Forage management and persistence (objective 2); Component 4, Problem areas, Grazing impacts on ecosystems (objectives 1 and 2)and Management, behavior, and production of grazing livestock (objectives 1, 2, and 3); and Component 5, Integrated management of weeds and other pests (objective 1).

Impacts
(N/A)

Publications

  • Boggs, K., Sturdy, M., Rinella, D.J., Rinella, M.J. 2008. White Spruce Regeneration Following a Major Spruce Beetle Outbreak in Forests on the Kenai Peninsula, Alaska. Forest Ecology and Management 255:3571-3579.
  • Wylie, B.K., Fosnight, E.A., Gilmanov, T.G., Frank, A.B., Morgan, J.A., Haferkamp, M.R., Myers, T.P. 2007. Adaptive data-driven models for estimating carbon fluxes in the northern great plains. Remote Sensing of Environment 106:399-413.
  • Rinella, M.J., Pokorny, M.L., Rekaya, R. 2007. Grassland Invader Responses to Realistic Changes in Native Species Richness. Ecological Applications 17(6):1824¿1831.


Progress 10/01/06 to 09/30/07

Outputs
Progress Report Objectives (from AD-416) 1. Quantify relative impacts of climatic variation and livestock grazing on sustainability of Northern Great Plains rangeland ecosystems and develop management strategies to ameliorate selected economic and ecological risks resulting from adverse impacts. a. Quantify impacts of spring drought and above average summer rainfall on primary productivity and proportion of plant species groups in the biomass. b. Quantify impacts of climatic conditions and varying livestock grazing tactics on primary productivity and plant species composition and diversity. c. Quantify impacts of grazing management strategies on soil C, CO2 flux, above- and below-ground biomass, and plant species composition. d. Quantify impacts of varying abiotic and biotic factors, particularly animal mediated impacts, on rate and extent of invasion and control of noxious weeds into rangeland dominated landscapes. e. Research and develop ecologically and economically sound rangeland restoration technologies for restoring degraded, weed infested rangeland ecosystems. 2. Quantify impacts of management tactics designed to improve the supply of quality forage in relation to nutritional needs of cattle on performance of grazing cattle and related economic indicators. a. Determine persistence and potential grazing value of experimental cultivars of seeded perennial forages on non-irrigated pastures for early spring or fall grazing, with emphasis on wheatgrasses and wildryes, b. Quantify impacts of varying seasons of calving (late winter, early spring, and late spring) on rangeland-based beef cattle production traits. c. Determine profit and associated annual risk as a function of season of calving and subsequent variations in post-weaning management strategies. 3. Evaluate in vitro gas production techniques to estimate seasonal variation in forage quality and predict performance in rangeland-based beef cow production systems. Approach (from AD-416) Field-laboratory studies will evaluate how plants respond to grazing and environmental stress. Role of rangelands and management tactics in regulating atmospheric carbon dioxide flux will be assessed by measuring temporal changes in plant biomass, soil carbon and water, and carbon dioxide fluxes with chambers. Long-term impacts of environment on ecological condition will be assessed by evaluating changes in plant species composition inside and outside livestock exclosures and evaluating changes in herbage production and rooting dynamics with short- term droughts applied with a rain-out shelter. Fundamental life history, autecological studies will be initiated to quantify roles that varying abiotic and biotic factors play in regulating the rate and extent of invasion and control of noxious weeds. Fundamental understandings of important ecological processes will be researched, developed, expanded, and ultimately incorporated into rangeland restoration technologies. The potential role of planted forages will be studied by monitoring herbage growth dynamics, cattle diets, and weight gains. Late winter, early spring, and late spring calving seasons will be evaluated for their effect on biologic and economic measures of rangeland beef production. In vitro gas production techniques will be used to evaluate seasonal variations in forage quality and results will be evaluated for their ability to accurately predict performance of grazing cattle. Accomplishments Fire-Induced Grasshopper Control Grasshoppers can consume more than 20% of the forage in the western United States, but also play important ecological roles in nutrient cycling and as nutritious prey. This research was the first to link field observations of rangeland insect populations following fire to mechanisms related to below-ground egg mortality. Fires occurring in areas with at least 3100 kg ha¿1 plant biomass would be expected to significantly reduce populations of Ageneotettix deorum, a shallow egg- laying pest species, but not Melanoplus sanguinipes, a deeper egg-laying pest species. No A. deorum eggs hatched in 86% of the trials exposed to fire intensities observed with 4500 kg ha¿ 1 of plant biomass. Results promote prescription development for a natural grasshopper control method with less impact on non-target species than pesticides and explain mechanisms by which fire may interact with other insects. Research was published in Ecological Entomology and transferred to numerous customers in support of NP 205 Component, Ecosystems and their Sustainable Management, while addressing Problem Area, Ecosystem Processes. Beef Heifer Development in Three Seasons of Calving Altering dates of calving and weaning to match cow nutritional requirements with forage quality dynamics impacts calf weight at weaning. This may affect subsequent management needs of heifer calves in anticipation of their entry into the breeding herd. We evaluated the impact of differing nutrient patterns from birth until first breeding on weight gain and reproductive performance of heifers born into mid-winter, early spring, or late spring calving systems and weaned at different ages. Heifers from varied calving, pre- and post-weaning management strategies performed similarly in initial reproductive performance and subsequent calf production, even though growth patterns and body weight at breeding differed. This suggests there are a wide variety of options available for rearing heifers. This research supports NP 205 Component, Grazing Management: Livestock Production and the Environment, while addressing Problem Area, Management, Behavior, and Production of Grazing Livestock. Technology Transfer Number of New CRADAS and MTAS: 1 Number of Web Sites managed: 2 Number of Non-Peer Reviewed Presentations and Proceedings: 11 Number of Newspaper Articles,Presentations for NonScience Audiences: 31

Impacts
(N/A)

Publications

  • Branson, David H. and Vermeire, Lance T. 2007. Grasshopper egg mortality mediated by oviposition tactics and fire intensity. Ecological Entomology. 32:128-134.
  • Grings, E.E., Phillips, W.A., Short, R.E., Mayeux Jr, H.S., Heitschmidt, R. K. 2006. Post-weaning performance of steers from varying calving and weaning strategies in montana. Professional Animal Scientist 22:386-391.
  • Kruse, R.E., Tess, M.W., and Heitschmidt, R.K. 2007. Drought management for the Northern Great Plains. I. A practical predictor of annual forage production. Professional Animal Scientist 23:224-233.
  • Kruse, R.E., Tess, M.W., and Heitschmidt, R.K. 2007. Drought management in the Northern Great Plains. II. Evaluation of alternative strategies for cow-calf enterprises. Professional Animal Scientist 23:234-245.
  • Phillips, W.A., Grings, E.E., Short, R.E., Heitschmidt, R.K., Coleman, S.W. , Mayeux Jr, H.S. 2006. Impact of calving season on stocker and feedlot performance. Professional Animal Scientist 22:392-400.
  • Rinella, M.J., Luschei, E.C. 2007. Hierarchial bayesian methods estimate invasive weed impacts at pertinent spatial scales. Biological Invasions 9:545-558.
  • Robins, J.G., Waldron, B.L., Vogel, K.P., Berdhal, J.D., Haferkamp, M.R., Jensen, K.B., Jones, T.A., Mitchell, R., Kindiger, B.K. 2007. Characterization of Testing Locations for Developing Cool-Season Grass Species. Crop Science 47:1004-1012.
  • Grings, E.E., Geary, T.W., Short, R.E., MacNeil, M.D. 2007. Beef Heifer Development Within Three Calving Systems. Journal of Animal Science 85:2048-2058.


Progress 10/01/05 to 09/30/06

Outputs
Progress Report 1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? Why does it matter? The grazing livestock industry is the largest agricultural industry in the Northern Great Plains relative to land resource (60 million ha) and gross financial returns. But because of its low-input extensive nature, it is continually subjected to high levels of ecological and economic risk. Rangeland agriculturalists' (i.e., graziers') sustainability is tied closely to their ability to manage high levels of ecological and economical uncertainty over time and space. These uncertainties stem largely from the effects that temporal changes in climatic conditions both short- (e.g., periodic drought) and long-term (e.g., climate change), and spatial changes in topographic and edaphic factors have on quantity and quality of forage produced. This is a very serious problem because the grazing livestock industry is the primary commercial industry in the Northern Great Plains and adoption of effective risk aversion management strategies is paramount to both the ecological and social fabric of the entire region. Specific objectives are to: 1) quantify relative impacts of climatic variation, livestock grazing, and fire on the sustainability of Northern Great Plains rangeland ecosystems and develop management strategies to ameliorate economic and ecological risks. Specifically, we are quantifying impacts of spring drought, above average summer and fall precipitation, grazing, and fire on herbage production, plant species composition and diversity, and rates of carbon sequestration; 2) quantifying effectiveness of management tactics designed to enhance the supply of quality forage throughout the year and economic well-being. Specifically, we are evaluating persistence and potential grazing value of experimental cultivars of seeded perennial forages with emphasis on wheatgrasses and wildryes, quantifying impacts of varying seasons of calving (late winter, early spring, and late spring) on rangeland-based beef cattle production traits, and determining profit and associated annual risk as a function of season of calving and subsequent variations in post-weaning management strategies; 3) evaluating in vitro gas production techniques to improve accuracy of forage quality estimates and prediction of animal performance in rangeland-based livestock production systems; and 4) identifying fundamental factors affecting ingress of invasive weeds, particularly leafy spurge, into rangeland ecosystems and quantifying the modifying effects of livestock grazing on these processes and potential use of livestock grazing as a management tool. The overall goal of the National Program 205, Rangeland Pastures and Forages, is to provide appropriate technologies and management strategies to sustain our Nation's grazing lands. Working under this program plan and in concert with the Food Animal Production National Program (NP 101), the mission of Fort Keogh LARRL is to research and develop ecologically and economically sustainable range animal management systems. Research is aligned with the following components of the NP 205 Action Plan and addresses the stated problem areas: Component 1, Problem areas, Ecological Processes (objective 1), Ecological and economical sustainability (objective 1), and Decision support (objectives 1 and 2); Component 2, Problem areas, Improving forages for livestock production (objective 2)and Overcoming limitations to plant growth and development (objective 2); Component 3, Problem area, Forage management and persistence (objective 2); Component 4, Problem areas, Grazing impacts on ecosystems (objectives 1 and 2)and Management, behavior, and production of grazing livestock (objectives 1, 2, and 3); and Component 5, Integrated management of weeds and other pests (objective 1). 2. List by year the currently approved milestones (indicators of research progress) Year 1 (FY 2003) 1a. Design rainout-irrigation system. 1b. Initiate summer fire and post-fire grazing research. 1c. Collect vegetation, soil, and CO2 flux data from untreated plots. 2a. Summer fallow areas for new seedings and plant if seed supplies and environment allow. Collect final biomass data from forage nurseries. 2b. Apply post-weaning growth treatments to heifers born in varied seasons. Measure milk production in heifers born in varied seasons and raised using varied post-weaning growth strategies. 3. Conduct laboratory analysis on cattle diet samples. 4. (new) Hire 2 scientists, a weed ecologist and an ruminant nutritionist. Year 2 (FY 2004) 1a. Initiate drought/irrigation treatments and vegetation sampling to quantify impacts of a spring drought and wet summer on herbage production and plant species composition. 1b. Collect and process data from paired plots grazed or excluded from livestock grazing for 10 years. Apply post-fire grazing and second-year summer fire treatments. 1c. Sample vegetation, soil, CO2 flux, and environmental variables. Apply December burn and moderate grazing treatments in May and June. 2a. Summer fallow nursery site and pastures for planting new entries. Collect forage, diet, and animal weights in conjunction with study of heifers grazing seeded forages and native rangeland. 2b. Apply post-weaning growth treatments to heifers born in varied seasons. Measure milk production in heifers born in varied seasons and raised using varied post-weaning growth strategies. 2c. Conduct economic analysis on data collected from season of calving study conducted from 1998 through 2001. 3. Conduct laboratory analysis on cattle diet samples and relate in vitro gas production measures to animal performance and statistically analyze and publish these data. 4. (new) Initiate evaluation of rumen fermentation and the biotic impacts of noxious weeds with an in vitro gas production system. Initiate studies on spotted knapweed-and leafy spurge-infested areas to determine the impact of various management practices on weed and grass populations. Year 3 (FY 2005) 1a. Monitor post-treatment effects to quantify variable, post-treatment response patterns relative to productivity and species composition. 1b. Apply second-year post-fire grazing. Collect data on population growth rates and competition parameters of forage grasses. 1c. Continue applying grazing treatments, sampling vegetation, soil, CO2 flux, and environmental variables, and begin laboratory analysis of vegetation and soil samples. 2a. Plant nursery. Collect forage, diet, and animal weights in conjunction with grazing seeded forages and native rangeland. 2b. Apply post-weaning growth treatments to heifers born in varied seasons. Analyze data on heifer development programs and submit summary to refereed journal. 2c. Submit summary of economic analysis on season of calving studies to a refereed journal. 3. Conduct laboratory analysis of gas production from simulated diets. 4. Continue evaluation of ruminal fermentation and the biotic impact of noxious weeds with an in vitro gas production system. Construct exclosures and initiate grazing trails designed to quantify impacts of cattle, sheep, and cattle + sheep grazing on establishment and propagation of leafy spurge and spotted knapweed. Year 4 (FY 2006) 1a. Data will be summarized, analyzed, interpreted, and submitted for publication in refereed journal. 1b. Data on short-term response to summer fire and post-fire grazing will be summarized, analyzed, interpreted, and submitted for publication in refereed journal. Data will become available on short-term effects of summer fire on grasshopper density and composition. 1c. Continue application of treatments, data collection, and lab analysis. Data will become available on the effect of grazing and burning on vegetation dynamics, soil, and CO2 flux. 2a. Continue collecting forage, diet, and animal weight data in conjunction with study of heifers grazing seeded forages and native rangeland. Continue data collection on the impacts of integrated grazing of seeded forages and rangeland on heifer growth. 2b. Measure milk production on heifers born in varied seasons. Conduct laboratory analysis on samples from heifer development studies. 3. Conduct laboratory analysis on simulated diet samples. Data from the study of impact of noxious weeds on in vitro gas production will be summarized, analyzed, interpreted, and submitted for publication in a refereed journal. 4. Conduct grazing trials to assess impact of livestock grazing on ingress of invasive weeds. Continue data collection on population growth rates and competition parameters of noxious weeds and forage grasses, and use to develop models that predict the response of noxious weeds to weed management strategies. 5. (new) Develop new CRIS proposal. Year 5 (FY 2007) 1a. Continue drought/irrigation treatments and vegetation sampling to quantify impacts of autumn drought and irrigation on herbage production and plant species composition. Objectives expanded following completion of summer irrigation research. 1b. Data on 2-year recovery following summer fire and grazing and fire- induced changes in mineral dynamics and surface litter decomposition will be summarized, analyzed, interpreted, and submitted for publication in refereed journal. 1c. Data on the effect of grazing and burning on vegetation dynamics, soil, and CO2 flux will be summarized, interpreted and submitted to a refereed journal. 2a. Continue data collection on the impacts of integrated grazing of seeded forages and rangeland on heifer growth. 2b. Measure milk production on heifers born in varied seasons (sufficiently addressed with earlier results, will not be continued). Analyze and publish data on heifer development programs. 3. Analyze and publish data on in vitro gas production studies. 4. Continue data collection on population growth rates and competition parameters of noxious weeds and forage grasses, and use to develop models that predict the response of noxious weeds to weed management strategies. 4a List the single most significant research accomplishment during FY 2006. Drought Risk Assessment Drought is an inherent factor in the northern plains and creates substantial risks for rangeland management and livestock production. Drought management decisions are often delayed with the hope that summer rains may compensate for spring forage losses. Large amounts of summer rain can increase forage, but increases were insufficient to offset more than 50% of reductions caused by spring drought and the probability of receiving the 6 inches of water applied in July and August is less than 1%. Results allow rangeland managers to make timely drought management decisions to reduce risks for livestock enterprises and rangeland resources. Research was published in Rangeland Ecology & Management and transferred to numerous customers in support of NP 205 Component, Ecosystems and their Sustainable Management, while addressing Problem Area, Forecasting and Risk Assessment. 4b List other significant research accomplishment(s), if any. Modeling Weed Dynamics Identifying optimal rangeland weed management strategies requires predicting how candidate strategies will affect the production of weeds and livestock forage. We used data from field experiments to develop a model that predicts weed and forage responses to management actions. Model accuracy was tested by comparing model predictions to data from published studies. The model fairly accurately predicted published weed and forage data. Therefore, we concluded the model could improve decision-making with respect to rangeland weeds. Research was published in Weed Science and transferred to customers in support of NP 205 Component, Ecosystems and their Sustainable Management, while addressing Problem Area, Forecasting and Risk Assessment. 5. Describe the major accomplishments to date and their predicted or actual impact. In support of the broad Goal 6: Protect and enhance the Nations natural resource base and environment and the specific Objective 5.1: Provide science-based knowledge and education to improve the management of forest, rangelands, and pastures of the ARS 2003-2007 Strategic Plan, and the ARS National Rangeland, Pasture, and Forages program component: 1.) Ecosystems and their sustainable management, a. Developed simple, user-friendly, proactive decision support system for managing rangelands during periods of drought. Ranchers are keen to use the system as it provides early warning of impending conditions that, if not addressed, will significantly reduce economic profits (Problem Area Forecasting and Risk Assessment). b. We documented, using repeat photography and in cooperation with Utah State University, that the general ecological condition of Northern Great Plains rangelands have generally improved over the past 75+ years. Specific phenomena noted were: 1) a dramatic increase in Ponderosa pine across the landscape; 2) increased human impacts on landscapes because of tillage, road construction, haying, etc.; and 3) some site-specific increases in non-indigenous species, particularly crested wheatgrass and yellow clover. Results were published as a 91 page, USDA-ARS Conservation Research Report. Initial printing was 1,000 reports all of which were distributed within 6 months of publication to requesting individuals. Thus, a second printing of 1000 reports was required to meet consumer interests (Problem Area Monitoring and Assessment Technologies). c. A research review and analysis was conducted and published in BioScience on the role and impacts of prairie dogs on Great Plains grasslands. Cooperating scientists were from South Dakota State University and Montana State University. Review showed that contrary to many claims: 1) historical number of prairie dogs is probably inflated; 2) bison, antelope, etc., do not have an over-whelming affinity for prairie dog colonies; 3) prairie dogs do not inherently enhance herbage quality; and 4) prairie dogs do severely restrict livestock production. Black-tailed prairie dog listing under Endangered Species Act has since been determined unwarranted. Results provide a check against unsubstantiated claims in the politically charged issue of prairie dog management and their use in future petitions for listing (Problem Area Managing Degraded Systems). d. Historically, wildfires were common during summer but their potential role as a management tool is not well understood because of the perceived dangers associated with summer wildfires. To this end, we have been studying the effects of summer fire on Northern Great Plains rangelands, and to date our data shows that prescribed summer fires can be used to reduce abundance of sagebrush, prickly pear, and annual brome without causing undue harm to the dominant perennial grasses. Moreover, preliminary results show that properly managed grazing during the first year following fire does not significantly impact the ecological health of these grasslands (Problem Area - Managing Degraded Systems). e. We determined that Northern Great Plains rangelands have considerable capacity to grow forage during summer if precipitation is abundant. However, less than half of the forage lost by spring drought was offset by more than doubling water in July and August. When we combined these findings with the probabilities of receiving substantial summer precipitation, we concluded that it is risky to expect substantial forage production after July 1 in this region (Problem Area Forecasting and Risk Assessment). f. We used data from field experiments to develop a model that predicts weed and forage responses to management actions. Model accuracy was tested by comparing model predictions to data from published studies. The model accurately predicted published weed and forage data. Therefore, we concluded the model could improve weed management decision- making (Problem Area, Forecasting and Risk Assessment). 2) Plant Resources a. A fundamental problem in the Northern Great Plains is a general absence of an abundance of high quality forage in early spring and fall. To alleviate this problem, seeded cool-season forages are often grazed. But a basic question associated with the use of seeded forages is how much is that worth in terms of enhancing livestock performance? Studies at this location show that seeded forages can improve weight gains of growing heifers dramatically during spring and considerably during fall. Still, it is imperative that imperative that graziers compare costs associated with stand establishment and maintenance to the increase in revenues resulting from increased animal performance (Problem Area Improving Forages for Livestock Production). b. A predictive model of rangeland forage quality was developed using growing degree days and percentage of dead plant material thereby allowing rangeland managers to assess forage quality in an easy and timely manner (Problem Area Improving Forages for Livestock Production). 3) Grazing Management: Livestock Production and the Environment a. Quantified the effects of livestock grazing versus livestock exclusion on annual productivity and biodiversity of rangelands. Diversity varied by year, but was similar between grazing treatments. Livestock exclusion increased the presence of annual bromes and introduced species as a whole. There was no indication that livestock exclusion increased biomass or improved plant community integrity, suggesting proper grazing is essential for maintaining the health and well-being of Northern Great Plains rangelands (Problem Area Grazing Impacts on Ecosystems). b. Studies evaluating the effects of different seasons of calving (i.e. , February, April, and June) on herd productivity and economic returns show that: 1) calving season affects milk production, and subsequently calf weight gains, in direct relation to forage/diet quality; 2) calving season and age of calf at weaning interact to affect post-weaning performance including carcass characteristics; and 3) June calving tended to be the most profitable of the 3 seasons of calving because of lowered input costs (Problem Area Ecologically and Economically Sustainable Systems). c. Quantified the effects of varying livestock grazing systems on herbage production and plant species composition at moderate rates of stocking. Found that response to varying grazing systems was minimal during 7-year period thereby countering the argument that certain grazing systems are superior to all others. Results help ranchers better evaluate the economic and ecological costs and benefits derived from implementing varying grazing systems (Problem Area Ecologically and Economically Sustainable Systems). 6. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? We are constantly transferring technology on preliminary and final results of all studies. This information was shared during FY2006 with producers, state and federal agency personnel, and scientists through more than 35 presentations at local and regional meetings and the annual meetings of the Society for Range Management, American Society of Animal Sciences, Western Section of American Society of Animal Sciences, Soil and Water Conservation Society, Western Society of Weed Science. 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below). Cows prefer Green Conservation Update, Custer County Conservation District, Spring 2006, 11:5. "Bye-Bye Hoppers" Beef Magazine, April 2006 Issue, page 40. "Green Acres" Agricultural Research Magazine, February 2006, page 19. Invited instruction on Grazing management in a rangeland environment, for US Forest Service Rangeland Management for Line Officers Training School, Milford, PA, April 2005 "Scientists Exchange Knowledge" Miles City Star, November 2005.

Impacts
(N/A)

Publications

  • Phillips, W.A., Grings, E.E., Short, R., Heitschmidt, R.K., Mayeux, H.S. 2006. Effect of calving date on stocker and feedlot performance of calves born in the northern great plains and finished in the southern great plains [abstract]. Journal of Animal Science. p. 71.
  • Rinella, M.J., Sheley, R.L. 2005. Models that predict invasive weed and grass dynamics: 2. Accuracy evaluation. Weed Science 53:605-614.
  • Rinella, M.J., Sheley, R.L. 2005. Models that predict invasive weed and grass dynamics: 1. Model development. Weed Science 53:586-593.
  • Rinella, M.J., Sheley, R.L. 2006. Using light attenuation to estimate leafy spurge impacts on forage production. Rangeland Ecology and Management 59(4):431-437.
  • Rose, J.L., Vermeire, L.T., Wester, D.B. 2006. Short-term effects of summer fire and post-fire grazing in the northern great plains. Society for Range Management Meeting Abstracts #314.
  • Vermeire, L.T., Wester, D.B., Mitchell, R., Fuhlendorf, S.D. 2005. Fire and grazing effects on wind erosion, soil water content, and soil temperature. Journal of Environmental Quality 34:1559-1565.
  • Vermeire, L.T., Heitschmidt, R.K., Haferkamp, M.R. 2006. Grazing and livestock exclusion effects on northern plains diversity and heterogeneity. Society for Range Management Meeting Abstracts #365.
  • Muscha, J.M., Hild, A.L. 2006. Biological soil crusts in grazed and ungrazed wyoming sagebrush steppe. Journal of Arid Environments 67:195-207.
  • Richardson, K.D., Kelly, W.L., Reil, M.S., Waterman, R.C., Lodge-Ivey, S.L. 2006. Effects of leafy spurge (euphorbia esula) on ruminant gas production and in vitro digestion. Western Section of Animal Science Proceedings 57:36-39.
  • Richardson, K.D., Kelly, W.L., Reil, M.S., Waterman, R.C., Lodge-Ivey, S.L. 2006. Effects of leafy spurge (euphorbia esula) on ruminant gas production and in vitro digestion. Journal of Animal Science Supplement 84(Suppl. 2):139.
  • Richardson, K.D., Silva, J.B., Waterman, R.C., Kelly, W.L., Reil, M.S., Ivey, S.L. 2006. Comparative effects of leafy spurge on rumen bacterial ecology of the bovine and ovine.. American Society for Microbiology Abstract #N-213.
  • Haferkamp, M.R., Macneil, M.D. 2004. Annual brome seed germination in the northern great plains: an update. Forest Service Proceedings RMRS-P-31. p. 115-119.
  • Haferkamp, M.R., Macneil, M.D., Grings, E.E., Klement, K.D. 2005. Heifer production on rangeland and seeded forages in the northern great plains. Rangeland Ecology and Management 58:495-504.
  • Haferkamp, M.R., Macneil, M.D., Vermeire, L.T., Muscha, J.M. 2006. Measuring carbon dioxide flux over northern great plains rangeland. Society for Range Management Meeting Abstracts #140.
  • Heitschmidt, R.K., Vermeire, L.T. 2006. Can abundant summer precipitation counter losses in herbage production caused by spring drought?. Rangeland Ecology and Management 59:392-399.
  • Heitschmidt, R.K., Vermeire, L.T. 2006. The significance of summer precipitation in the northern great plains. Society for Range Management Meeting Abstracts #160.
  • Branson, D.H., Vermeire, L.T. 2006. Effects of summer fire and post-fire grazing on grasshopper abundance and species composition. Society for Range Management. Abstract 59:44.
  • Grings, E.E., Blummel, M., Sudekum, K.H. 2005. Methodological considerations in using gas production techniques for estimating ruminal microbial effciencies for silage-based diets. Animal Feed Science And Technology 123-124:527-545.
  • Grings, E.E., Short, R., Klement, K.D., Geary, T.W., MacNeil, M.D., Haferkamp, M.R., and Heitschmidt, R.K. 2005. Calving system and weaning age effects on cow and preweaning calf performance in the Northern Great Plains. Journal of Animal Science 83:2671-2683.
  • Grings, E.E. 2006. Use of in vitro gas production techniques to evaluate associative effects of forages. Society for Range Management Meeting Abstracts #134.
  • Grings, E.E. 2006. The language of rangeland science. Rangelands 28(2):36- 37


Progress 10/01/04 to 09/30/05

Outputs
1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter? The grazing livestock industry is the largest agricultural industry in the Northern Great Plains relative to land resource (60 million ha) and gross financial returns. But because of its low-input extensive nature, it is continually subjected to high levels of ecological and economic risk. Rangeland agriculturalists' (i.e., graziers') sustainability is tied closely to their ability to manage high levels of ecological and economical uncertainty over time and space. These uncertainties stem largely from the effects that temporal changes in climatic conditions both short- (e.g., periodic drought) and long-term (e.g., climate change), and spatial changes in topographic and edaphic factors have on quantity and quality of forage produced. This is a very serious problem because the grazing livestock industry is the primary commercial industry in the Northern Great Plains and adoption of effective risk aversion management strategies is paramount to both the ecological and social fabric of the entire region. Specific objectives are to: 1) quantify relative impacts of climatic variation, livestock grazing, and fire on the sustainability of Northern Great Plains rangeland ecosystems and develop management strategies to ameliorate economic and ecological risks. Specifically, we are quantifying impacts of spring drought, above average summer and fall precipitation, grazing, and fire on herbage production, plant species composition and diversity, and rates of carbon sequestration; 2) quantifying effectiveness of management tactics designed to enhance the supply of quality forage throughout the year and economic well-being. Specifically, we are evaluating persistence and potential grazing value of experimental cultivars of seeded perennial forages with emphasis on wheatgrasses and wildryes, quantifying impacts of varying seasons of calving (late winter, early spring, and late spring) on rangeland-based beef cattle production traits, and determining profit and associated annual risk as a function of season of calving and subsequent variations in post-weaning management strategies; 3) evaluating in vitro gas production techniques to improve accuracy of forage quality estimates and prediction of animal performance in rangeland-based livestock production systems; and 4) identifying fundamental factors affecting ingress of invasive weeds, particularly leafy spurge, into rangeland ecosystems and quantifying the modifying effects of livestock grazing on these processes and potential use of livestock grazing as a management tool. The overall goal of the National Program 205, Rangeland Pastures and Forages, is to provide appropriate technologies and management strategies to sustain our Nation's grazing lands. Working under this program plan and in concert with the Food Animal Production National Program (NP 101), the mission of Fort Keogh LARRL is to research and develop ecologically and economically sustainable range animal management systems. More specifically, this research meets the goals of the NP 205 Action Plan in the following ways: Component 1, Problem areas, Ecological Processes (objective 1), Ecological and economical sustainability (objective 1), and Decision support (objectives 1 and 2); Component 2, Problem areas, Improving forages for livestock production (objective 2) and Overcoming limitations to plant growth and development (objective 2); Component 3, Problem area, Forage management and persistence (objective 2) ; Component 4, Problem areas, Grazing impacts on ecosystems (objectives 1 and 2) and Management, behavior, and production of grazing livestock (objectives 1, 2, and 3); and Component 5, Integrated management of weeds and other pests (objective 1). 2. List the milestones (indicators of progress) from your Project Plan. Year 1 (2003) 1a. Design rainout-irrigation system. 1b. Initiate summer fire and post-fire grazing research. 1c. Collect vegetation, soil, and CO2 flux data from untreated plots. 2a. Summer fallow areas for new seedings and plant if seed supplies and environment allow. Collect final biomass data from forage nurseries. 2b. Apply post-weaning growth treatments to heifers born in varied seasons. Measure milk production in heifers born in varied seasons and raised using varied post-weaning growth strategies. 3. Conduct laboratory analysis on cattle diet samples. 4.(new)Hire 2 scientists, a weed ecologist and an ruminant nutritionist. Year 2 (2004) 1a. Initiate drought/irrigation treatments and vegetation sampling to quantify impacts of a spring drought and wet summer on herbage production and plant species composition. 1b. Collect and process data from paired plots grazed or excluded from livestock grazing for 10 years. Apply post-fire grazing and second- year summer fire treatments. 1c. Sample vegetation, soil, CO2 flux, and environmental variables. Apply December burn and moderate grazing treatments in May and June. 2a. Summer fallow nursery site and pastures for planting new entries. Collect forage, diet, and animal weights in conjunction with study of heifers grazing seeded forages and native rangeland. 2b. Apply post-weaning growth treatments to heifers born in varied seasons. Measure milk production in heifers born in varied seasons and raised using varied post-weaning growth strategies. 2c. Conduct economic analysis on data collected from season of calving study conducted from 1998 through 2001. 3. Conduct laboratory analysis on cattle diet samples and relate in vitro gas production measures to animal performance and statistically analyze and publish these data. 4.(new)Initiate evaluation of rumen fermentation and the biotic impacts of noxious weeds with an in vitro gas production system. Initiate studies on spotted knapweed-and leafy spurge-infested areas to determine the impact of various management practices on weed and grass populations. Year 3 (2005) 1a. Monitor post-treatment effects to quantify variable, post- treatment response patterns relative to productivity and species composition. 1b. Apply second-year post-fire grazing. Collect data on population growth rates and competition parameters of forage grasses. 1c. Continue applying grazing treatments, sampling vegetation, soil, CO2 flux, and environmental variables, and begin laboratory analysis of vegetation and soil samples. 2a. Plant nursery. Collect forage, diet, and animal weights in conjunction with grazing seeded forages and native rangeland. 2b. Apply post-weaning growth treatments to heifers born in varied seasons. Analyze data on heifer development programs and submit summary to refereed journal. 2c. Submit summary of economic analysis on season of calving studies to a refereed journal. 3. Conduct laboratory analysis of gas production from simulated diets. 4.(new)Continue evaluation of ruminal fermentation and the biotic impact of noxious weeds with an in vitro gas production system. Construct exclosures and initiate grazing trails designed to quantify impacts of cattle, sheep, and cattle + sheep grazing on establishment and propagation of leafy spurge and spotted knapweed. Year 4 (2006) 1a. Data will be summarized, analyzed, interpreted, and submitted for publication in refereed journal. 1b. Data on short-term response to summer fire and post-fire grazing will be summarized, analyzed, interpreted, and submitted for publication in refereed journal. Data will become available on short-term effects of summer fire on grasshopper density and composition. 1c. Continue application of treatments, data collection, and lab analysis. Data will become available on the effect of grazing and burning on vegetation dynamics, soil, and CO2 flux. 2a. Continue collecting forage, diet, and animal weight data in conjunction with study of heifers grazing seeded forages and native rangeland. Continue data collection on the impacts of integrated grazing of seeded forages and rangeland on heifer growth. 2b. Measure milk production on heifers born in varied seasons. Conduct laboratory analysis on samples from heifer development studies. 3. Conduct laboratory analysis on simulated diet samples. Data from the study of impact of noxious weeds on in vitro gas production will be summarized, analyzed, interpreted, and submitted for publication in a refereed journal. 4.(new)Conduct grazing trials to assess impact of livestock grazing on ingress of invasive weeds. Continue data collection on population growth rates and competition parameters of noxious weeds and forage grasses, and use to develop models that predict the response of noxious weeds to weed management strategies. 5. Develop new CRIS proposal. Year 5 (2007) New field and laboratory studies will be initiated in accordance with newly approved CRIS project. All data from previous CRIS studies will be analyzed and submitted for publication in both refereed journals and various user-friendly venues. 3a List the milestones that were scheduled to be addressed in FY 2005. For each milestone, indicate the status: fully met, substantially met, or not met. If not met, why. 1. 1a. Monitor post-treatment effects to quantify variable, post-treatment response patterns relative to productivity and species composition. Manuscript was submitted (i.e., 1-year ahead of schedule) quantifying impacts of spring drought, followed by wet summer, on herbage production and plant species composition and second study was initiated to quantify impacts of fall precipitation on following years herbage production. Milestone Fully Met 2. 1b. Apply second-year post-fire grazing. Milestone Fully Met 3. 1b. Collect data on population growth rates and competition parameters of forage grasses. Milestone Fully Met 4. 1c. Continue applying grazing treatments, sampling vegetation, soil, CO2 flux, and environmental variables, and begin laboratory analysis of vegetation and soil samples. Milestone Fully Met 5. 2a. Plant nursery. Milestone not met because of inadequate seed sources and the retirement of key cooperating plant breeders, nursery work was abandoned. Milestone Not Met Progress slowed by resource limitation (human,fiscal,equipment, etc. 6. 2a. Collect forage, diet, and animal weights in conjunction with grazing seeded forages and native rangeland (Milestone not met). Because of continuing drought conditions, forage growth was inadequate to support experiment. Milestone Not Met Progress slowed by resource limitation (human,fiscal,equipment, etc. 7. 2b. Apply post-weaning growth treatments to heifers born in varied seasons. Milestone Fully Met 8. 2b. Analyze data on heifer development programs and submit summary to refereed journal Data were analyzed and presented as proceeding paper and talk at scientific society meeting. Work on refereed journal manuscript continues. Milestone Substantially Met 9. 2c. Submit summary of economic analysis on season of calving studies to a refereed journal. Refereed journal manuscript is nearly complete but waiting for submission of associated manuscripts of field data used in economic analyses. Milestone Substantially Met 10. 3. Conduct laboratory analysis of gas production from simulated diets. Milestone Fully Met 11. 4. (new)Continue evaluation of ruminal fermentation and the biotic impact of noxious weeds with an in vitro gas production system. Milestone Fully Met 12. 4b. Construct exclosures and initiate grazing trails designed to quantify impacts of cattle, sheep, and cattle + sheep grazing on establishment and propagation of leafy spurge and spotted knapweed. Milestone Fully Met 3b List the milestones that you expect to address over the next 3 years (FY 2006, 2007, and 2008). What do you expect to accomplish, year by year, over the next 3 years under each milestone? Year 4 (2006) New CRIS project will be written. 1a. Data will be summarized, analyzed, interpreted, and submitted for publication in refereed journal. 1b. Data on short-term response to summer fire and post-fire grazing will be summarized, analyzed, interpreted, and submitted for publication in refereed journal. Data will become available on short-term effects of summer fire on grasshopper density and composition. 1c. Continue application of treatments, data collection, and lab analysis. Data will become available on the effect of grazing and burning on vegetation dynamics, soil, and CO2 flux. 2a. Continue collecting forage, diet, and animal weights in conjunction with grazing seeded forages and native rangeland. Continue data collections on the impacts of integrated grazing of seeded forages and rangeland on heifer growth. 2b. Post weaning growth treatments will be applied to heifers born in varied seasons and data will be collected on growth and subsequent calf performance. Milk production will only be measured if data analysis conducted in FY2005 indicates an impact of heifer development programs on milk yield. Laboratory analysis on samples from heifer development studies will be collected. 3. Laboratory analysis on simulated diet samples will be conducted. Data from the study of impact of noxious weeds on in vitro gas production will be summarized, analyzed, interpreted, and submitted for publication in a refereed journal. 4. Data will be collected on population growth rates and competition parameters of noxious weeds and forage grasses, and these data will be used to develop models that predict the response of noxious weeds to weed management strategies. Data will become available on the effects of livestock grazing on noxious weed invasions. Year 5 (2007) All data from previous CRIS studies will be summarized, analyzed, and manuscripts written for submission to refereed journals. Research results will also be presented in user-friendly formats via oral and written communications for purposes of transferring recently developed technologies. Year 1 (2007) Field research will be initiated in accordance with established and approved objectives and goals of new CRIS project. Year 2 (2008) First year data will be summarized and on-going studies will be continued and modified as appropriate. 4a What was the single most significant accomplishment this past year? Rangeland Carbon Sequestration The role of rangelands in regulating atmospheric carbon dioxide concentrations is a critical issue in global climate change research. To better understand this phenomenon, we studied the effects of autumn burning and short-term moderate grazing in May or June on carbon dioxide flux during 2004 and 2005. Preliminary results from the April-June period of the study show that varibles that best described day time carbon dioxide flux were green leaf area, soil water, and photosynthetic active solar radiation with soil water being the only variable significantly affected by burning or grazing. Thus weather, particularly precipitation, appears to exert primary control on carbon dioxide exchange in the Northern Great Plains. Findings provide governmental land use policy makers needed information on the role of rangelands and management strategies in regulating carbon dioxide, reportedly a major factor of climate change. 4b List other significant accomplishments, if any. Drought Management Decision Support System Drought is a fundamental trait of rangelands and sustainable rangeland management requires the development of effective drought management strategies. Using frequent clipping data from a series of studies, we found that: 1) perennial grass production in much of the Northern Great Plains is tied closely to spring time precipitation and loosely tied to fall precipitation, and as such 2) about 90% of perennial grass production is normally completed by July 1. This is largely because summer precipitation is very limited in this region. Moreover, using calculated precipitation probabilities (http://hprcc.unl.edu/index.html), rangeland managers can also determine the probabilities of receiving substantial precipitation at any given time of the year. Thus, ranchers in this region can assess with considerable confidence, their annual forage situation by early July thereby giving them an opportunity to respond to drought conditions long before they deplete their entire forage base. Livestock Exclusion May Reduce Integrity of Native Flora Effects of 10 years of moderate grazing by livestock and livestock exclusion were shown to be similar in terms of current-year biomass, diversity, and heterogeneity. Species composition was largely similar between treatments, with the exception that in the latter half of the period, livestock exclusion increased introduced species, predominantly annual bromes. Livestock exclusion may not be a preferred method of preserving Northern Great Plains rangelands because such treatment tend not to increase either current-year biomass or diversity and may be negatively affecting the integrity of native flora. Data have been analyzed and reported at one scientific meeting and in one technical report. Developing New Methods for Assessing Rumen Efficiency We collaborated on a study evaluating the relationship between in vitro and in vivo estimates of efficiency of rumen microbial biomass and microbial protein production. Efficiency of microbial biomass production in the rumen is an important factor affecting efficiency of feed utilization. This characteristic has been difficult to study, especially in extensive grazing situations, because of the need for surgically- altered animals and frequent sample collection. In vitro gas production measures were combined with substrate degradability values to estimate microbial efficiency. Measures taken at substrate specific times, based upon their individual fermentation kinetics, provided values that were correlated to in vivo measures of microbial efficiency. Use of laboratory techniques to estimate rumen microbial efficiency could be used to advance our understanding of ruminant nutrition at a more rapid pace than in vivo studies. Predicting Effects of Invasive Weeds on Rangeland Herbage Production Rangeland managers often employ management strategies that suppress weed populations in hopes that forage production will increase. The magnitude of grass response to rangeland weed suppression helps determine if these management efforts are warranted. Unfortunately, techniques for predicting grass response to weed suppression are not widely available. This is partly because data on weed abundances per unit area are needed to predict grass response, and gathering these data with currently available techniques is extremely time-consuming. In cooperation with ARS researchers at Burns, OR, we found a rapidly measured index (< 2 minutes per sample location) that is highly correlated with weed (i.e. leafy spurge Euphorbia esula L.) abundance per unit area. The index is based on the light attenuation leafy spurge caused when it was grown in combination with perennial grasses in 2 field experiments. We used the index to develop a probabilistic model that predicts grass response to leafy spurge suppression. Predictive ability of the model was assessed by comparing model predictions to data from 3 published experiments where herbicides suppressed leafy spurge. The herbicide experiment data fell within the range of values (i.e. credibility interval) the model predicted even though the model development site and the herbicide experiment sites were separated by several hundred kilometers and were measured during different years. Therefore, we conclude that the models predictive capability is not compromised dramatically by spatial and temporal variation. This light attenuation model will be useful for quantifying weed impacts and helping managers determine which weed management strategies will be cost effective. 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. In support of the broad Goal 6: Protect and enhance the Nations natural resource base and environment and the specific Objective 5.1: Provide science-based knowledge and education to improve the management of forest, rangelands, and pastures of the ARS 2003-2007 Strategic Plan, and the ARS National Rangeland, Pasture, and Forages program component: 1.) Ecosystems and their sustainable management, a. Developed simple, user-friendly, proactive decision support system for managing rangelands during periods of drought. Ranchers are keen to use the system as it provides early warning of impending conditions that, if not addressed, will significantly reduce economic profits (Problem Area Forecasting and Risk Assessment). b. We documented, using repeat photography and in cooperation with Utah State University, that the general ecological condition of Northern Great Plains rangelands have generally improved over the past 75+ years. Specific phenomena noted were: 1) a dramatic increase in Ponderosa pine across the landscape; 2) increases in human impacts on landscapes because of increased tillage, road construction, haying, etc.; and 3) some site- specific increases in non-indigenous species, particularly crested wheatgrass and yellow clover. Results were published as a 91 page, USDA- ARS Conservation Research Report. Initial printing was 1,000 reports all of which were distributed within 6 months of publication to requesting individuals. Thus, a second printing of 1000 reports was required to meet consumer interests (Problem Area Monitoring and Assessment Technologies) . c. A research review was conducted and published in BioScience magazine on the role and impacts of prairie dogs on Great Plains grasslands. Cooperating scientists were from South Dakota State University and Montana State University. Review showed that contrary to many claims: 1) historical number of prairie dogs is probably inflated; 2) bison, antelope, etc., do not have an over-whelming affinity for prairie dog colonies; 3) prairie dogs do not inherently enhance herbage quality; and 4) prairie dogs do severely restrict livestock production (Problem Area Managing Degraded Systems). d. Historically, wildfires were common during summer but their potential role as a management tool is not well understood because of the perceived dangers associated with summer wildfires. To this end, we have been studying the effects of summer fire on Northern Great Plains rangelands, and to date our data shows that prescribed summer fires can be used to reduce abundance of sagebrush without causing undue harm to the dominant perennial grasses. Moreover, preliminary results show that properly managed grazing during the first year following fire does not significantly impact the ecological health of these grasslands (Problem Area - Managing Degraded Systems). e. We determined that Northern Great Plains rangelands have considerable capacity to grow forage during summer if precipitation is abundant. Still, when we combined these findings with the probabilities of receiving substantial summer precipitation, we concluded that it is risky to expect substantial forage production after July 1 in this region (Problem Area Forecasting and Risk Assessment). 2) Plant Resources a. A fundamental problem in the Northern Great Plains is a general absence of an abundance of high quality forage in early spring and fall. To alleviate this problem, seeded cool-season forages are often grazed. But a basic question associated with the use of seeded forages is how much is that worth in terms of enhancing livestock performance? Studies at this location show that seeded forages can improve weight gains of growing heifers dramatically during spring and considerably during fall. Still, it is imperative that imperative that graziers compare costs associated with stand establishment and maintenance to the increase in revenues resulting from increased animal performance (Problem Area Improving Forages for Livestock Production). b. A predictive model of rangeland forage quality was developed using growing degree days and percentage of dead plant material thereby allowing rangeland managers to assess forage quality in an easy and timely manner (Problem Area Improving Forages for Livestock Production). 3) Grazing Management: Livestock Production and the Environment a. Quantified the effects of varying livestock grazing tactics on annual productivity and biodiversity of rangelands. In contrast to no graze or ungrazed lands, grazed lands did not reduce productivity nor did they reduce biodiversity. In fact, there are indications that diversity of ungrazed sites is in a downward trend thereby suggesting proper grazing is essential for maintaining the health and well-being of Northern Great Plains rangelands (Problem Area Grazing Impacts on Ecosystems). b. Studies evaluating the effects of different seasons of calving (i.e., February, April, and June) on herd productivity and economic returns show that: 1) calving season affects milk production, and subsequently calf weight gains, in direct relation to forage/diet quality; 2) calving season and age of calf at weaning interact to affect post-weaning performance including carcass characteristics; and 3) June calving tended to be the most profitable of the 3 seasons of calving because of lowered input costs (Problem Area Ecologically and Economically Sustainable Systems). c. Quantified the effects of varying livestock grazing systems on herbage production and plant species composition at moderate rates of stocking. Found that response to varying grazing systems was minimal during 7-year period thereby countering the argument that certain grazing systems are superior to all others. Results help ranchers better evaluate the economic and ecological costs and benefits derived from implementing varying grazing systems (Problem Area Ecologically and Economically Sustainable Systems). 6. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? We are constantly transferring technology on preliminary and final findings of all studies. This information was shared during FY2005with producers (e.g., LARRL Customer Focus Group, tour of Beef Improvement Federation, MSU Extension Service meetings, Montana Governors Winter Grazing Seminar, etc.), agency personnel (e.g., Forest Service, BLM, NRCS, and MSU Extension agents, etc.), and scientists (i.e., presentations at annual meetings of the Society for Range Management, American Society of Animal Sciences, Western Section of American Society of Animal Sciences, American Weed Society, etc.). 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below). Invited to give presentation on "Geographic Distribution of Native Legumes in the United States" as introductory talk in a session on native legumes at the 2005 Society for Range Management Meeting. Invited by Organizing Committee, Satellite Workshop, XX International Grasslands to make presentation entitled Do You Have to Run Out of Forage Before Managing?, Glasgow, Scotland, 2005. Gave presentation on geographic distribution of native legumes at the 2005 SRM meetings. Miles City Star Articles - Local Newspaper - Some articles picked up by other newspapers in surrounding communities - most articles printed in the Farmer edition sent out to all rural residents in the surrounding area. 24 Nov. 04 Drought test backs push for early decisions 3 Feb. 05 Heavy calves not worth the cost: Reukauf 17 Feb. 05 New program to reward good management 24 Mar. 05 Weed invasion dynamics probed 12 May 05 Study eyes grazing impacts after wild fires 19 May 05 Grass tentiny killing some area cattle 26 May 05 Scientist wins award 7 July 05 Conditions converge to allow range rest 14 July 2005 Bromes plentiful on this year's range 14 July 05 Study probes herbicide cheatgrass impact 24 Aug 05 Million dollar rain 24 Aug 05 Rains actually skew some Ft. Keogh experiments Popular Publications: Allen, V., Heitschmidt, R.K., Sollenberger, L. Grazing systems and strategies. In: C. Jerry Nelson (ed.). Forages, Vol. II. Iowa State Univ. Press, Ames, Iowa. 2004. (Book Chapter) Gilmanov, T.G., M.W. Demment, B.K. Wylie, E.A. Laca, K. Akshalov, D.D. Baldocchi, L. Belelli, J.A. Bradford, R.L. Coulter, W.A. Dugas, W.E. Emmerich, L.B. Flanagan, A.B. Frank, M.R. Haferkamp, D.A. Johnson, T.P. Meyers, J.A. Morgan, M. Nasyrov, C.E. Owensby, M.S. Pekour, K. Pilegaard, N.Z. Saliendra, M.J. Sanz, P.L. Sims, J.-F. Soussana, L.L. Tieszen, and S. B. Verma. 2005. Quantification of the CO2 exchange in grassland ecosystems of the world using tower measurements, modeling, and remote sensing. XX International Grassland Congress 2005 Proceedings. (Proceedings) Grings, E.E., A.J. Roberts,and T.W. Geary. 2005. Milk yield of beef heifers from three calving systems. Proc. West. Sec. Amer. Soc. Anim. Sci. 56:131-134. Vermeire, L.T. (ed.). 2005. Fort Keogh Livestock and Range Research Laboratory 2005 Research Update. 57 pgs. Vermeire, L.T., Wallace, M.C., Mitchell, R. 2004. Elk population assessment in western states and Canadian provinces. Rangelands 26:29-33.

Impacts
(N/A)

Publications

  • Heitschmidt, R.K., Klement, K.D., Haferkamp, M.R., 2005. Interactive effects of drought and grazing on northern great plains rangelands. Rangeland Ecology and Management 58:11-19.
  • Grings, E.E., Short, R.E., Heitschmidt, R.K. 2004. Post-weaning production of steers from varying calving and weaning strategies. Journal of Animal Science Supplement 82(2):111-112.
  • Heitschmidt, R.K., Byington, E.K. 2005. The role of the agricultural research service in sustaining rangeland ecosystems. Society for Range Management Meeting Abstracts 58th Meeting #164. CD only. Fort Worth, Texas.
  • Kruse, R.E., Tess, M.W., Grings, E.E., Short, R.E., Heitschmidt, R.K., Phillips, W.A., Mayeux Jr, H.S. 2004. Evaluation of beef cattle operations utilizing different seasons of calving, weaning stratigies, post-weaning management, and retained ownership. Journal of Animal Science Supplement 82(2) :111.
  • Vermeire, L.T., Heitschmidt, R.K., Haferkamp, M.R. 2005. Northern plains plant community response to 10 years of livestock exclusion. Ecological Society of America Abstracts 90:661.
  • Vermeire, L.T., Mitchell, R., Fuhlendorf, S.D., Wester, D.B. 2005. Patch burning and grazing effects on southern mixed prairie plant communities. Society for Range Management Meeting Abstracts #357 on CD.
  • Muscha, J.M., Vermeire, L.T., Haferkamp, M.R. 2005. Effect of fire and grazing on vegetation and biological soil crusts in eastern montana. Society for Range Management Meeting Abstracts 58:199.
  • Heitschmidt, R.K., Vermeire, L.T. 2005. An ecological and economic risk avoidance drought management decision support system. In: J.A. Milne (ed.) Pastoral systems in marginal environments. XXth International Grasslands Congress July 2005. p. 178.
  • Rose, J.L., Vermeire, L.T., Wester, D.B. 2005. First year response to summer fire and post-fire. Society for Range Management Abstracts #58. grazing effects in northern mixed prairie. Meeting Abstract.
  • Gilmanov, T.G., Tieszen, L.L., Wylie, B.K., Flanagan, L.B., Frank, A.B., Haferkamp, M.R., Meyers, T.P., Morgan, J.A. 2005. Integration of CO2 flux and remotely sensed data for primary production and ecosystem respiration analyses in the Northern Great Plains: Potential for quantitative spatial extrapolation. Global Ecology and Biogeography 14:271-292.
  • Haferkamp, M. R., MacNeil, M. D., Grings, E. E. Predicting Nitrogen Content in the Northern Mixed-Grass Prairie Rangeland Ecology & Management. 2005. 58: 155-160.
  • Haferkamp, M.R. 2005. Geographic distribution of legumes in rangelands and woodlands of the united states. Society for Range Management Meeting Abstracts #145 on CD.
  • Rose, J.L., Vermeire, L.T., Wester, D.B. 2005. First year richness and frequency response to summer fire and post-fire grazing. Society for Range Management Meeting Abstracts #291. On CD only.
  • Grings, E.E., Waterman, R.C. 2005. Inoculum source effects on in vitro gas production of forages. American Society of Animal Science 83(Suppl 1):148.
  • Grings, E.E., Blummel, M. 2005. Application of rates of fermentation to prediction of forage intake. Journal of Animal Science Supplement 83(Suppl. 1):238.


Progress 10/01/03 to 09/30/04

Outputs
1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter? The grazing livestock industry is the largest agricultural industry in the Northern Great Plains relative to land resource (60 million ha) and gross financial returns. But because of its low-input extensive nature, it is continually subjected to high levels of ecological and economic risk. Rangeland agriculturalists' (i.e., graziers') sustainability is tied closely to their ability to manage high levels of ecological and economical uncertainty over time and space. These uncertainties stem largely from the effects that temporal changes in climatic conditions both short- (e.g., periodic drought) and long-term (e.g., climate change), and spatial changes in topographic and edaphic factors have on quantity and quality of forage produced. This is a very serious problem because the grazing livestock industry is the primary commercial industry in the Northern Great Plains and adoption of effective risk aversion management strategies is paramount to both the ecological and social fabric of the entire region. Specific objectives are to: 1) quantify relative impacts of climatic variation, livestock grazing, and fire on sustainability of Northern Great Plains rangeland ecosystems and develop management strategies to ameliorate selected economic and ecological risks resulting from adverse impacts. Specifically, we are quantifying impacts of spring drought and above average summer rainfall on primary productivity and proportion of plant species groups in the biomass, impacts of climatic conditions, varying livestock grazing tactics, fire and invasive weeds on primary productivity and plant species composition and diversity, and impacts of grazing management strategies on soil C, CO2 flux, above- and below- ground biomass, and plant species composition. 2.) quantify impacts of management tactics designed to improve the supply of quality forage in relation to nutritional needs of cattle on performance of grazing cattle and related economic indicators. Specifically, we are evaluating persistence and potential grazing value of experimental cultivars of seeded perennial forages on non-irrigated pastures for early spring or fall grazing, with emphasis on wheatgrasses and wildryes, quantifying impacts of varying seasons of calving (late winter, early spring, and late spring) on rangeland-based beef cattle production traits, and determining profit and associated annual risk as a function of season of calving and subsequent variations in post-weaning management strategies; and 3.) evaluate in vitro gas production techniques to estimate seasonal variation in forage quality and predict performance in rangeland-based beef cow production systems. The overall goal of the National Program 205, Rangeland Pastures and Forages, is to provide appropriate technologies and management strategies to sustain our Nation's grazing lands. Working under this program plan and in concert with the Food Animal Production National Program (NP 101), the mission of Fort Keogh LARRL is to research and develop ecologically and economically sustainable range animal management systems that ultimately meet consumer needs. More specifically, this research meets the goals of the NP 205 Action Plan in the following ways: Component 1, Problem areas, Ecological Processes (objective 1), Ecological and economical sustainability (objective 1), and Decision support (objectives 1 and 2); Component 2, Problem areas, Improving forages for livestock production (objective 2) and Overcoming limitations to plant growth and development (objective 2); Component 3, Problem area, Forage management and persistence (objective 2) ; and Component 4, Problem areas, Grazing impacts on ecosystems (objectives 1 and 2) and Management, behavior, and production of grazing livestock (objectives 1, 2, and 3). 2. List the milestones (indicators of progress) from your Project Plan. Year 1 (2003) 1a. Design rainout-irrigation system. 1b. Initiate summer fire and post-fire grazing research. 1c. Collect vegetation, soil, and CO2 flux data from untreated plots. 2a. Summer fallow areas for new seedings and plant if seed supplies and environment allow. Collect final biomass data from forage nurseries. 2b. Apply post-weaning growth treatments to heifers born in varied seasons. Measure milk production in heifers born in varied seasons and raised using varied post-weaning growth strategies. 3. Conduct laboratory analysis on cattle diet samples. Year 2 (2004) 1a. Initiate drought/irrigation treatments and vegetation sampling to quantify the impact of a spring drought and wet summer on aboveground net primary productivity and plant species composition. 1b. Collect and process data from paired plots grazed or excluded from livestock grazing for 10 years. Apply post-fire grazing and second-year summer fire treatments. Initiate studies on spotted knapweed- and leafy spurge-infested areas to determine the impact of various management practices on weed and grass populations. 1c. Sample vegetation, soil, CO2 flux, and environmental variables. Apply December burn and moderate grazing treatments in May and June. 2a. Summer fallow nursery site and pastures for planting new entries. Collect forage, diet, and animal weights in conjunction with study of heifers grazing seeded forages and native rangeland. 2b. Apply post-weaning growth treatments to heifers born in varied seasons. Measure milk production in heifers born in varied seasons and raised using varied post-weaning growth strategies. 2c. Conduct economic analysis on data collected from season of calving study conducted from 1998 through 2001. 3. Conduct laboratory analysis on cattle diet samples and relate in vitro gas production measures to animal performance and statistically analyze and publish these data. Initiate evaluation of rumen fermentation and the biotic impacts of noxious weeds with an in vitro gas production system. Year 3 (2005) 1a. Monitor post-treatment effects to quantify variable, post-treatment response patterns relative to productivity and species composition. 1b. Apply second-year post-fire grazing. Collect data on population growth rates and competition parameters of noxious weeds and forage grasses. Initiate a field study that quantifies the effects of livestock grazing on noxious weed invasions. 1c. Continue applying grazing treatments, sampling vegetation, soil, CO2 flux, and environmental variables, and begin laboratory analysis of vegetation and soil samples. 2a. Plant nursery. Collect forage, diet, and animal weights in conjunction with grazing seeded forages and native rangeland. 2b. Apply post-weaning growth treatments to heifers born in varied seasons. Analyze data on heifer development programs and submit summary to refereed journal. 2c. Submit summary of economic analysis on season of calving studies to a refereed journal. 3. Conduct laboratory analysis of gas production from simulated diets. Continue evaluation of ruminal fermentation and the biotic impact of noxious weeds with an in vitro gas production system. Evaluate dietary additives and their associative effect with ruminal fermentation. Year 4 (2006) 1a. Data will be summarized, analyzed, interpreted, and submitted for publication in refereed journal. 1b. Data on short-term response to summer fire and post-fire grazing will be summarized, analyzed, interpreted, and submitted for publication in refereed journal. Data will become available on short-term effects of summer fire on grasshopper density and composition. Continue data collection on population growth rates and competition parameters of noxious weeds and forage grasses, and use to develop models that predict the response of noxious weeds to weed management strategies. Data will become available on the effects of livestock grazing on noxious weed invasions. 1c. Continue application of treatments, data collection, and lab analysis. Data will become available on the effect of grazing and burning on vegetation dynamics, soil, and CO2 flux. 2a. Continue collecting forage, diet, and animal weight data in conjunction with study of heifers grazing seeded forages and native rangeland. Continue data collection on the impacts of integrated grazing of seeded forages and rangeland on heifer growth. 2b. Measure milk production on heifers born in varied seasons. Conduct laboratory analysis on samples from heifer development studies. 3. Conduct laboratory analysis on simulated diet samples. Data from the study of impact of noxious weeds on in vitro gas production will be summarized, analyzed, interpreted, and submitted for publication in a refereed journal. Year 5 (2007) 1a. Manuscript will be published and user-friendly, risk aversion, drought management strategies will be formalized and presented in varying technology transfer venues. 1b. Assess changes in productivity and species composition over time following summer fire and post-fire grazing. Complete models that predict response of noxious weeds and associated forage grasses to weed management strategies. Initiate analysis for identifying effects of livestock grazing on noxious weed invasions. 1c. Data will be summarized, analyzed, interpreted, and submitted for publication in refereed journal. 2a. Continue data collection on the impacts of integrated grazing of seeded forages and rangeland on heifer growth. 2b. Measure milk production on heifers born in varied seasons. Analyze and publish data on heifer development programs. 3. Analyze and publish data on in vitro gas production studies. Manuscript will be published on the study of impact of noxious weeds on in vitro gas production, and discovery of applicable information will be disseminated in various technology transfer venues. 3. Milestones: A. List the milestones (from the list in Question #2) that were scheduled to be addressed in FY2004. How many milestones did you fully or substantially meet in FY2004 and indicate which ones were not fully or substantially met, briefly explain why not, and your plans to do so. 1a. Initiate drought/irrigation treatments and vegetation sampling to quantify the impact of a spring drought and wet summer on aboveground net primary productivity and plant species composition. (Milestone fully met) 1b. Collect and process data from paired plots grazed or excluded from livestock grazing for 10 years. (Milestone fully met.) Apply post-fire grazing and second-year summer fire treatments. (Milestone fully met.) Initiate studies on spotted knapweed- and leafy spurge-infested areas to determine the impact of various management practices on weed and grass populations. (Milestone fully met.) 1c. Sample vegetation, soil, CO2 flux, and environmental variables on plots, and apply December burn and moderate grazing treatments in May and June. (Milestone fully met.) 2a. Summer fallow nursery site and pastures for planting new entries. (Milestone fully met.) Collect forage, diet, and animal weights in conjunction with study of heifers grazing seeded forages and native rangeland. (Milestone was not met. An extremely dry autumn 2003 and spring 2004 did not allow adequate forage growth for grazing heifers on the seeded pastures. We plan to begin grazing in spring 2005 and conduct this study during 2005, 2006, and 2007). 2b. Apply post-weaning growth treatments to heifers born in varied seasons. (Milestone fully met.) Measure milk production in heifers born in varied seasons and raised using varied post-weaning growth strategies. (Milestone fully met.) 2c. Conduct economic analysis on data from season of calving study conducted from 1998 through 2001. (Milestone fully met.) 3. Conduct laboratory analysis on cattle diet samples and relate in vitro gas production measures to animal performance and statistically analyze and publish these data. (Milestone not met due to delays in laboratory analyses associated with laboratory remodeling.) Initiate evaluation of rumen fermentation and the biotic impacts of noxious weeds with an in vitro gas production system. (Milestone fully met.) B. List the milestones (from the list in Question #2) that you expect to address over the next 3 years (FY2005, FY2006, & FY2007). What do you expect to accomplish, year by year, over the next 3 years under each milestone? Year 3 (2005) 1a. Monitor post-treatment effects to quantify variable, post-treatment response patterns relative to productivity and species composition. 1b. Apply second-year post-fire grazing. Collect data on population growth rates and competition parameters of noxious weeds and forage grasses. Initiate a field study that identifies the effects of livestock grazing on noxious weed invasions. 1c. Continue applying grazing treatments, sampling vegetation, soil, CO2 flux, and environmental variables, and begin laboratory analysis of vegetation and soil samples. 2a. Plant nursery. Collect forage, diet, and animal weights in conjunction with grazing seeded forages and native rangeland. 2b. Post-weaning growth treatments will be applied to heifers born in varied seasons and data on growth and subsequent calf performance will be collected. Data on heifer development programs and their effect on lactation in first-calf heifers will be analyzed and published. 2c. Economic analysis on data from season of calving studies will be submitted to a refereed journal. 3. Laboratory analysis of gas production from simulated diets will be conducted. Continue an evaluation of ruminal fermentation and the biotic impact of noxious weeds when titrated into an in vitro gas production system. Evaluate dietary additives and their associative effect with ruminal fermentation. Year 4 (2006) 1a. Data will be summarized, analyzed, interpreted, and submitted for publication in refereed journal. 1b. Data on short-term response to summer fire and post-fire grazing will be summarized, analyzed, interpreted, and submitted for publication in refereed journal. Data will become available on short-term effects of summer fire on grasshopper density and composition. Data will be collected on population growth rates and competition parameters of noxious weeds and forage grasses, and these data will be used to develop models that predict the response of noxious weeds to weed management strategies. Data will become available on the effects of livestock grazing on noxious weed invasions. 1c. Continue application of treatments, data collection, and lab analysis. Data will become available on the effect of grazing and burning on vegetation dynamics, soil, and CO2 flux. 2a. Continue collecting forage, diet, and animal weights in conjunction with grazing seeded forages and native rangeland. Continue data collections on the impacts of integrated grazing of seeded forages and rangeland on heifer growth. 2b. Post weaning growth treatments will be applied to heifers born in varied seasons and data will be collected on growth and subsequent calf performance. Milk production will only be measured if data analysis conducted in FY2005 indicates an impact of heifer development programs on milk yield. Laboratory analysis on samples from heifer development studies will be collected. 3. Laboratory analysis on simulated diet samples will be conducted. Data from the study of impact of noxious weeds on in vitro gas production will be summarized, analyzed, interpreted, and submitted for publication in a refereed journal. Year 5 (2007) 1a. Manuscript will be published and user-friendly, risk aversion; drought management strategies will be formalized and presented in varying technology transfer venues. 1b. Assess changes in productivity and species composition over time following summer fire and post-fire grazing. Complete models that predict the response of noxious weeds and associated forage grasses to weed management strategies. Initiate analysis for identifying effects of livestock grazing on noxious weed invasions. 1c. Data will be summarized, analyzed, interpreted, and submitted for publication in refereed journal. 2a. Continue collecting forage, diet, and animal weights in conjunction with study on heifers grazing seeded forages and native rangeland. Continue data collection on the impacts of integrated grazing of seeded forages and rangeland on heifer growth. 2b. Data on development programs for heifers will be analyzed and published. 3. Data on in vitro gas production studies will be analyzed and published. Manuscript will be published on the study of impact of noxious weeds on in vitro gas production, and discovery of applicable information will be disseminated in various technology transfer venues. 4. What were the most significant accomplishments this past year? A. Single most significant accomplishment during FY2004 (one per Research (OOD) Project): Frequent clipping data from a series of primary productive studies were used to develop a proactive drought management strategy that assists rangeland agriculturalists (i.e. graziers) in managing rangeland based resources during periods of moderate to severe drought. Research established that 1) perennial grass production in much of the Northern Great Plains is tied closely to spring time precipitation and loosely tied to fall precipitation, and as such 2) about 90% of perennial grass production is normally completed by July 1. This is largely because summer precipitation is very limited in this region. Thus, ranchers in this region can assess, with some confidence, their annual forage production by July 1, thereby giving them an opportunity to respond to drought conditions long before they run entirely out of forage. B. Other significant accomplishment(s) if any: Concerns have arisen about the potential varied effects of grazing strategies on plant community composition and standing crop. Knowledge of community response to grazing strategies is required for producers, land-managing agencies, and scientists to sustain productive rangeland resources for desired products. USDA-ARS, Miles City, MT, assessed community response to 7 grazing strategies by measuring standing crop of plant functional groups 1 year before and after 6 years of grazing treatments. Data have been presented to producers and college students and are scheduled to be presented at a scientific meeting in January 2004 that indicate grazing strategies are secondary to weather for impacting plant communities on claypan sites. Rapid and inexpensive determination of biological value of rangeland forage is important for livestock producers to efficiently use forage resources. USDA-ARS, Miles City, MT, developed an equation to predict percent nitrogen in standing forage (April-October) from percent dead and cummulative degree days. This equation accounted for 75.9% of variation in percent N with prediction error variance of 0.026, and in validation studies N was predicted on another set of forage samples collected on different sites in different years with a resulting correlation between predicted and actual values of 0.79. Use of this equation would allow livestock producers to predict protein content of a grazingland resource without costly and time-consuming chemical analysis of forage samples. Herbage standing crop is an important measure of rangeland productivity and carrying capacity, but acquisition of accurate measurements is generally labor-intensive and locally destructive. USDA-ARS, Miles City, MT, tested visual obstruction (VO) throughout a growing season and across observers as a rapid, non-destructive estimation technique by regressing herbage standing crop on VO to develop predictive equations. Predictions were within 218 kg ha-1 of the true standing crop with 95% confidence, indicating accurate estimates can be achieved with reasonable precision for numerous applications. Land managers and researchers could benefit from rapid standing crop estimates using VO by reducing labor or increasing sampling for similar effort. C. Significant activities that support special target populations. None D. Progress Report opportunity to submit additional programmatic information to your Area Office and NPS (optional for all in-house ("D") projects and the projects listed in Appendix A; mandatory for all other subordinate projects). Invasive weeds reduce forage availability and plant species diversity in rangelands. Livestock producers need effective strategies for managing existing weed infestations and preventing new invasion. Two scientists have been added to this CRIS during FY2004, and their research is designed to improve our understanding of the impact of noxious weeds on rangeland vegetation and ruminal fermentation characteristics of ovine and bovine grazing weed infested areas on rangelands. Their initial efforts and future plans have been included in the milestones. 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. Preliminary analysis has been conducted by USDA-ARS, Miles City, MT, on the impacts of varying seasons of calving on rangeland-based beef cattle production traits using data collected in 1998 - 2001 under CRIS # 5434 31000 011 00 D. Data on the cow calf portion of this study has been reported at a scientific meeting and to local livestock producers, and results have been provided to researchers at Montana State University for evaluation of economic returns from the various production systems. Choice of calving seasons has significant impacts on both inputs and outputs to beef cattle operations and results need to be evaluated in the context of an individual operation. 6. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? We are constantly transferring technology on preliminary and final findings of all studies. This information has been shared with producers, agency personnel, and scientists verbally on field tours and at local, regional, and national meetings and through various publication avenues. Listed below are the tours and meetings associated with technology transfer. South Dakota State University Animal and Range Science Student's tour, LARRL,June 2004. NCBA Research and Education Committee tour, LARRL, July 2004. Consulted with users attending Zortman Weed Management Plan Meeting, Zortman, MT, May 24, 2004. Field Day, August 11, 2004, updates on current research and recent findings, Fort Keogh, Miles City, Montana. 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. "Fort Keogh Research Update," Sidney Ag Days, Sidney, MT, January 2004. "Tips on communicating rangeland ecology to the diverse audience," Society for Range Management annual meeting, Professional Issues Luncheon, Salt Lake City, UT, January 2004. "Models for invasive plant management," University of Washington, March 2004. "Invasive plants and wildlife," Society for Range Management Wildlife Habitat Committee news letter, 2004. "Use of fire in management of invasive weeds and restoration of historic plant communities," consultation with Theodore Roosevelt National Park, Medora, ND, April 2004. "Fire in the landscape," Fire Ecology Workshop, hosted by BLM, Miles City, MT, February 2004. "Annual brome seed germination in the Northern Great Plains: An update, " USDA Forest Service Proceedings RMRS-P-31, Seed and soil dynamics in shrubland ecosystems, p.115-119, February 2004. "Range robbers," Beef, annual brome research was reported by Clint Peck, Senior Editor, p. 14, March 2004. "A new concept in range cow supplement formulation," Beef Q&A, p. 6-7, March 2004. "Patch burning and grazing effects on soil characteristics in sand sagebrush mixed-grass prairie." 13th Wildland Shrub Symposium "Shrub dynamics: Fire and water," Lubbock, TX, August 2004. Invited member of USDA Forest Service National Grassland's Science Review Team. 2003 - 2004. "The Role of Grazers in Management of Invasive Weeds" Invasive Plant Control Symposium, Fort Lauderdale, FL. November 2003. Invited member of USDA NRCS program review panel. Fort Worth, TX. February 2004. Invited to serve as advisor/reviewer of North Dakota Agriculture Experiment Station rangeland research program. Hettinger, ND May 2004. "Drought," Congressman Denny Rehberg's Drought Management Symposium. Miles City, MT. June 2004. Backgrounding calves: options under drought conditions symposium. MSU Extension Service. Billings, MT August 2004.

Impacts
(N/A)

Publications

  • HAFERKAMP, M.R., MACNEIL, M.D. GRAZING EFFECTS ON CARBON DYNAMICS IN THE NORTHERN MIXED-GRASS PRAIRIE. ENVIRONMENTAL MANAGEMENT. 2004. Vol. 33. Suppl. 1. p. S462-S479.
  • Vermeire, L.T., Heitschmidt, R.K., Johnson, P.S., Sowell, B.F. 2004. The prairie dog story: do we have it right?. Bioscience 54(7)689-695.
  • ROSE, J., VERMEIRE, L.T., WESTER, D.B. ESTIMATING STANDING CROP WITH VISUAL OBSTRUCTION IN THE NORTHERN PLAINS. SOCIETY FOR RANGE MANAGEMENT MEETING ABSTRACTS. NO. 309. 2004.
  • VERMEIRE, L.T., HEITSCHMIDT, R.K., HAFERKAMP, M.R. NORTHERN PRAIRIE RESPONSE AFTER 6-YEAR EXPOSURE TO SEVEN GRAZING PRACTICES. SOCIETY FOR RANGE MANAGEMENT MEETING ABSTRACTS. No. 373. 2004.
  • Mcadoo, J.K., Vermeire, L.T., Gilgert, W. 2004. The other grazers. Rangelands. 26(3) 30-37
  • HEITSCHMIDT, R.K., KLEMENT, K.D., KRUSE, R.E. DROUGHT MANAGEMENT - DO YOU HAVE TO RUN OUT OF FORAGE BEFORE MANAGING?. SOCIETY FOR RANGE MANAGEMENT MEETING ABSTRACTS. 2004. ABSTRACT #138.
  • Heitschmidt, R.K., Vermeire, L.T., Grings, E.E. 2004. Is rangeland agriculture sustainable?. Journal of Animal Science 82(E. Suppl.):E138- E146.
  • Grings, E.E., Short, R.E., Haferkamp, M.R., Heitschmidt, R.K. 2004. Late summer protein supplementation for yearling cattle in the northern great plains. Journal of Range Management 57:358-364.
  • Blummel, M., Grings, E.E., Haferkamp, M.R. 2004. Fermentation profiles and degradability measurements in extrusa diet samples collected from brome- suppressed and undisturbed pastures and their relationship to weight gain of steers. Canadian Journal of Animal Science 84(1):105-111.
  • Grings, E.E., Short, R.E., Heitschmidt, R.K. 2004. Post-weaning production of steers from varying calving and weaning strategies. Western Section of Animal Science Proceedings 55:126-129.
  • Haferkamp, M.R., Macneil, M.D., Grings, E.E., Heitschmidt, R.K., Klement, K.D. 2004. Heifer production on rangeland and cool-season forages in the northern great plains. Agronomy Abstracts #508. On CD only.
  • GILMANOV, T.G., TIESZEN, L.L., WYLIE, B.K., FLANAGAN, L.B., FRANK, A.B., HAFERKAMP, M.R., MEYERS, T.P., AND MORGAN, J.A. 2004. TOWARDS SCALING-UP TOWER CO2 FLUX MEASUREMENTS IN GRASSLANDS OF THE NORTHERN GREAT PLAINS: PHENOMENOLOLGICAL MODELING USING FLUX PARTITIONING, VEGETATION INDICES AND GEOGRAPHIC INFORMATION SYSTEM (GIS). SOCIETY FOR RANGE MANAGEMENT MEETING ABSTRACTS #112.
  • Haferkamp, M.R., Macneil, M.D., Grings, E.E. 2004. Predicting quality of forage from northern great plains range sites. Society for Range Management Meeting Abstracts #124. CD Only.
  • FOX, W.E., HEITSCHMIDT, R.K., JOYCE, L. SUSTAINABLE RANGELANDS ROUNDTABLE (SRR) CRITERION: CONSERVATION AND MAINTENANCE OF PLANT AND ANIMAL RESOURCES ON RANGELANDS. INTERNATIONAL RANGELAND CONGRESS. 2003. p. 1955- 1957.
  • HEITSCHMIDT, R.K., HAFERKAMP, M.R., KLEMENT, K.D. GRAZING AND DROUGHT: EFFECTS ON QUANTITY OF FORAGE PRODUCED. SOCIETY FOR RANGE MANAGEMENT MEETING ABSTRACTS. 2003. ABSTRACT #107.
  • Kruse, R.E., Tess, M.W., Grings, E.E., Heitschmidt, R.K., Phillips, W.A., Mayeux Jr, H.S. 2004. Evaluation of beef cattle operations utilizing different seasons of calving, weaning stratigies, post-weaning management, and retained ownership. Western Section of Animal Science Proceedings 55:122-125.
  • Kruse, R.E., Tess, M.W., Grings, E.E., Short, R.E., Heitschmidt, R.K., Phillips, W.A., Mayeux Jr, H.S. 2004. Evaluation of beef cattle operations utilizing different seasons of calving, weaning stratigies, post-weaning management, and retained ownership. Journal of Animal Science Supplement 82(2):111.
  • Vermeire, L.T., Mitchell, R., Fuhlendorf, S.D., Gillen, R.L. 2004. Patch burning effects on forage utilization and grazing distribution. Journal of Range Management 57:248-252.
  • Vermeire, L.T., Mitchell, R., Fuhlendorf, S.D., Wester, D.B. 2004. Selective control of rangeland grasshoppers with prescribed fire. Journal Of Range Management v. 57. p. 29-33.
  • Mitchell, R., Vogel, K.P., Schmer, M.R., Vermeire, L.T. 2004. The medical approach to grassland assessment. Society for Range Management Meeting Abstracts. #259.
  • Rose, J.L., Vermeire, L.T., Wester, D.B. 2004. Effects of summer burning and stocking rate in the northern great plains. Research Highlights - 2004 Noxious Brush and Weed Control; Range, Wildlife, and Fisheries Management 35:26. Texas Tech University.


Progress 10/01/02 to 09/30/03

Outputs
1. What major problem or issue is being resolved and how are you resolving it? The grazing livestock industry is the largest agricultural industry in the Northern Great Plains relative to land resource (60 million ha) and gross financial returns. But because of its low-input extensive nature, it is continually subjected to high levels of ecological and economic risk. Rangeland agriculturalists' (i.e., graziers') sustainability is tied closely to their ability to manage high levels of ecological and economical uncertainty over time and space. These uncertainties stem largely from the effects that temporal changes in climatic conditions both short- (e.g., periodic drought) and long-term (e.g., climate change), and spatial changes in topographic and edaphic factors have on quantity and quality of forage produced. Specific objectives are to: 1. Quantify relative impacts of climatic variation, livestock grazing, and fire on sustainability of Northern Great Plains rangeland ecosystems and develop management strategies to ameliorate selected economic and ecological risks resulting from adverse impacts by (a) quantifying impacts of spring drought and above average summer rainfall on primary productivity and proportion of plant species groups in the biomass, (b) quantifying impacts of climatic conditions, varying livestock grazing tactics, and fire on primary productivity and plant species composition and diversity, and (c) quantifying impacts of grazing management strategies on soil C, CO2 flux, above- and below-ground biomass, and plant species composition; 2. Quantify impacts of management tactics designed to improve the supply of quality forage in relation to nutritional needs of cattle on performance of grazing cattle and related economic indicators by (a) determining persistence and potential grazing value of experimental cultivars of seeded perennial forages on non-irrigated pastures for early spring or fall grazing, with emphasis on wheatgrasses and wildryes, (b) quantifying impacts of varying seasons of calving (late winter, early spring, and late spring) on rangeland-based beef cattle production traits, and (c) determining profit and associated annual risk as a function of season of calving and subsequent variations in post-weaning management strategies; and 3. Evaluate in vitro gas production techniques to estimate seasonal variation in forage quality and predict performance in rangeland-based beef cow production systems. 2. How serious is the problem? Why does it matter? The grazing livestock industry is the largest commercial industry in the Northern Great Plains relative to land resources (60 million ha) and gross financial returns. Rangeland agriculture (i.e., grazing) is a high risk venture subject to considerable ecological and economic risks. Its sustainability is linked, therefore, to graziers' ability to manage these high levels of uncertainty over both time and space. The research proposed herein is designed to reduce levels of risk by: 1) improving our understanding of both the short- and long-term ecological consequences of climatic conditions, particularly drought, various grazing tactics, and fire; 2) developing proactive, early warning drought management strategies; 3) screening newly developed forage germplasm for persistence, potential productivity, and quality as they relate to grazing animals' performance and productivity; 4) developing improved methods for assessing forage quality; 5) determining the mechanisms responsible for differing levels of beef cattle production as a function of differing seasons of calving; and 6) identifying the economic merits of varying seasons of calving and subsequent post-weaning management strategies. In addition, a portion of this research is designed to quantify the capacity of Northern Great Plains rangelands to sequester and store atmospheric carbon. Such information is vital for the development of sound, national, climate change related, land management policies particularly in light of the vast amounts of rangelands located in the Northern Great Plains region as well as across the United States. Meeting these objectives will benefit the rangeland-based livestock industry, other land managers, researchers, and the public by reducing economic and ecological risk and enhancing sustainability of rangeland resources. Implementation of research findings will enable livestock producers to improve production efficiencies and maintain a more competitive posture in markets with economic limitations. Improved understanding of the impact of management decisions on other aspects of the operations, such as supplementation programs and grazing management systems, and on marketing strategies can be implied from the results. Feed evaluation systems closely linked to animal performance will provide improved information for decision-making processes. 3. How does it relate to the National Program(s) and National Program Component(s) to which it has been assigned? The overall goal of the National Program 205, Rangeland Pastures and Forages, is to provide appropriate technologies and management strategies to sustain our Nation's grazing lands. Working under this program plan and in concert with the Food Animal Production National Program (NP 101), the mission of Fort Keogh LARRL is to research and develop ecologically and economically sustainable range animal management systems that ultimately meet consumer needs. Specifically, research meets the goals of the NP 205 Action Plan in the following ways: Component Problem Area Objective 1 2 3 1 Ecosystem processes X Ecological and economical X sustainability Decision support X X 2 Improving forages for livestock production X Overcoming limitations to plant growth and X development 3 Forage management and persistence X 4 Grazing impacts on ecosystems X X Management, behavior, and production of X X X grazing livestock 4. What were the most significant accomplishments this past year? A. single Most Significant Accomplishment during past year Preliminary analysis has been conducted by USDA-ARS, Miles City, MT, on the impacts of varying seasons of calving on rangeland-based beef cattle production traits using data collected in 1998 - 2001 under CRIS # 5434 31000 011 00 D. Data on the cow calf portion of this study has been reported at a scientific meeting and to local livestock producers, and results have been provided to researchers at Montana State University for evaluation of economic returns from the various production systems. Choice of calving seasons has significant impacts on both inputs and outputs to beef cattle operations and results need to be evaluated in the context of an individual operation. B. Additional Accomplishments Concerns have arisen about the potential varied effects of grazing strategies on plant community composition and standing crop. Knowledge of community response to grazing strategies is required for producers, land-managing agencies, and scientists to sustain productive rangeland resources for desired products. USDA-ARS, Miles City, MT, assessed community response to 7 grazing strategies by measuring standing crop of plant functional groups 1 year before and after 6 years of grazing treatments. Data have been presented to producers and college students and are scheduled to be presented at a scientific meeting in January 2004 that indicate grazing strategies are secondary to weather for impacting plant communities on claypan sites. Rapid and inexpensive determination of biological value of rangeland forage is important for livestock producers to efficiently use forage resources. USDA-ARS, Miles City, MT, developed an equation to predict percent nitrogen in standing forage (April-October) from percent dead and cummulative degree days. This equation accounted for 75.9% of variation in percent N with prediction error variance of 0.026, and in validation studies N was predicted on another set of forage samples collected on different sites in different years with a resulting correlation between predicted and actual values of 0.79. Use of this equation would allow livestock producers to predict protein content of a grazingland resource without costly and time-consuming chemical analysis of forage samples. Herbage standing crop is an important measure of rangeland productivity and carrying capacity, but acquisition of accurate measurements is generally labor-intensive and locally destructive. USDA-ARS, Miles City, MT, tested visual obstruction (VO) throughout a growing season and across observers as a rapid, non-destructive estimation technique by regressing herbage standing crop on VO to develop predictive equations. Predictions were within 218 kg ha-1 of the true standing crop with 95% confidence, indicating accurate estimates can be achieved with reasonable precision for numerous applications. Land managers and researchers could benefit from rapid standing crop estimates using VO by reducing labor or increasing sampling for similar effort. 6. What do you expect to accomplish, year by year, over the next 3 years? FY 2004: Data will become available on the beef cattle back-grounding and finishing options for steers. Rearing options for heifers will be added to the available information on the impacts of season of calving on the cow-calf segment of the industry. This data will be evaluated in terms of both biological and economic impacts. Data will become available on above- ground production and species composition of paired sites where cattle have grazed or been excluded for 10 years. Data will be come available on the prediction of forage N from standing dead and cumulative degree days. These findings will provide information to producers allowing them to develop strategies that appropriately meet their management goals. Field research will be conducted to assess the impacts of spring drought, followed by above average summer precipitation, on native rangeland aboveground net primary production and plant species composition. FY 2005: Data will become available on the following: (1) milk production and calf growth traits of calves raised by cows under varied management conditions (season of calving and weaning and heifer growth strategies), (2) summer fire effects on grasshopper density and composition following summer fire, (3) impacts of integrated grazing of seeded forages and rangeland on heifer growth, and (4) the effects of spring drought, followed by above average summer precipitation, on native rangeland aboveground net primary production and plant species composition. These findings will provide information to producers allowing them to develop strategies that appropriately meet their management goals. FY 2006: Data will become available on the following: (1) impact of dietary diversity on ruminal fermentation characteristics from measurements with an in vitro gas production system; (2) the effects of summer fire and post-fire management on above- and below-ground characteristics of northern mixed prairie, including the frequency and density of shrubs and cacti, soil temperature and bulk density, standing crop, community composition, forage quality, diversity, cover, and litter, (3) impact of grazing intensity on carbon dioxide flux, and 4) the effects of spring drought, followed by above average summer precipitation, on rate of native rangeland recovery as they relate to primary productivity and livestock carrying capacities.This information will aid in our ability to predict animal performance in extensive rangeland-based environments and provide researchers, producers, and land-management agencies with regional information on community response and subsequent management recommendations following fire. 7. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? We are constantly transferring technology on preliminary and final findings of all studies. Particular emphasis this past year has been on providing ____ This information has been shared with producers, agency personnel, and scientists verbally on field tours and at local, regional, and national meetings and through various publication avenues. Listed below are the tours and meetings associated with technology transfer. Public Land's Council, Glasgow, MT February 2003 "Role of grazing management in the Northern Great Plains". Fort Keogh Customer Focus Group, LARRL, May 2003 Montana Stockgrower's Association tour, LARRL, June 2003 Alberta Canada Grazing Association tour, LARRL, July 2003 USDA Forest Service tour, Camp Crook, SD, July 2003 "Post-fire grazing management" U.S. Foreign Agriculture Service tour, LARRL, September 2003 USDA Forest Service tour, Ashland, MT, September 2003 "Grazing management and ecological condition" 8. List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: This does not replace your peer-reviewed publications listed below). "The role of fire in the northern Great Plains," Extension Agent and Specialist Symposium, Miles City, MT, September 2002. "Plant response to wildfire and post-burn management," County Extension Agent Training Program, Ekalaka, MT, February 2003. "Field demonstration of wildfire effects and site recovery," Sustainable Ag Training Program, Carter County, MT, May 2003 "Grazing management of the Long Pines Unit following the Kraft Springs fire," Camp Crook, SD. June 2003. American Society of Animal Science, Phoenix, AZ, June 2003. 'Effects of calving date and weaning age on cow and calf production in the Northern Great Plains.'

Impacts
(N/A)

Publications

  • GRINGS, E.E., SHORT, R.E., HEITSCHMIDT, R.K. EFFECTS OF CALVING DATE AND WEANING AGE ON COW AND CALF PRODUCTION IN THE NORTHERN GREAT PLAINS. JOURNAL OF ANIMAL SCIENCE SUPPLEMENT ABSTRACT #662. 2003. v. 81(SUPPL. 1). p. 169.
  • GRINGS, E.E., SHORT, R.E., HEITSCHMIDT, R.K. EFFECTS OF CALVING DATE AND WEANING AGE ON COW AND CALF PRODUCTION IN THE NORTHERN GREAT PLAINS. WESTERN SECTION OF ANIMAL SCIENCE PROCEEDINGS. 2003. v. 54. p. 335-338.
  • BLUMMEL, M.D., SHORT, R.E., GRINGS, E.E. COMPARISON OF ELK (CERVUS ELAPHUS) FECAL AND RUMEN MICROBIAL SUSPENSION TO PREDICT FEED DEGRADATION AND ADAPTATION. JOURNAL OF ANIMAL SCIENCE SUPPLEMENT. 2002. v. 80(SUPPL. 2). p. 143
  • LAWLER, T.L., TAYLOR, J.B., GRINGS, E.E., FINLEY, J.W., CATON, J.S. SELENIUM CONCENTRATION AND DISTRIBUTION IN RANGE FORAGES FROM FOUR LOCATIONS IN THE NORTHERN GREAT PLAINS. JOURNAL OF ANIMAL SCIENCE SUPPLEMENT. 2002. v. 80(SUPPL. 2). p. 115.
  • SVEJCAR, A.J., MAYEUX, JR., H.S., JOHNSON, D.A., FRANK, A.B., GILMANOV, T., ANGELL, R.F., MORGAN, J.A., SIMS, P.L., BRADFORD, J.A., SALIENDRA, N.Z., EMMERICH, W.E., SCHUMAN, G.E., HAFERKAMP, M.R., MITCHELL, K. CHARACTERIZATION OF THE CARBON STORAGE POTENTIAL OF US RANGELANDS WITH LONG-TERM CO2 FLUX MEASUREMENTS. SOC. RANGE MANAGEMENT ABSRACTS #283. 2003.
  • HEITSCHMIDT, R.K., VERMEIRE, L.T., GRINGS, E.E. IS RANGELAND AGRICULTURE SUSTAINABLE?. JOINT ABSTRACTS OF THE AMERICAN DAIRY SCIENCE AND SOCIETY OF ANIMAL SCIENCE. No. 118. 2003.
  • HEITSCHMIDT, R.K., KIRBY, D. RANGE PROGRAMS AT RISK. WESTERN FARMER STOCKMAN. p. 20. 2003.