1a. Objectives (from AD-416):
1) Develop practices and strategies for restoring perennial livestock forage systems, improving Great Basin rangelands using practices such as grazing management, soil treatments, seed coatings, and traditional restoration techniques. (NP215 Component 1; Problem Statements A and C) 2) Develop decision-support tools to enhance livestock production and precision restoration efforts, while also providing other ecosystem services, in different sites, climate conditions, and management systems on northwestern rangelands. (NP215 Component 1; Problem Statement B) 3) Develop effective precision restoration technologies and practices that target specific restoration needs, provide forage for productive grazing, and enhance sage grouse habitat. The technologies and practices could include areas such as engineering of improved means of site and seed preparation, new equipment or techniques for planting, development and use of amendments such as biochar, or others. (NP215 Component 1; Problem Statements B and C) 4) Develop improved land restoration, vegetation management strategies, and decision support tools. Research should include aspects of land manager decision-making priorities and system ecology/economics, and should result in expanded regional collaboration. (NP215 Component 1, Problem Statement 1A; NP215 Component 3, Problem Statement 3B)
1b. Approach (from AD-416):
The mission of the Burns unit is to provide the science for sound land and livestock management. This five-year plan builds on a rich history of research at this location, in some cases reaching back to the 1940's. The majority of the western U.S. is occupied by rangelands and the most efficient commodity production in the rangeland environment is grazing livestock. Sustainable management of western U.S. rangelands is facing threats of unprecedented scale from annual grass invasion, encroaching conifers, and an uncertain climate future. Simultaneously, the societal demand for a diversity of ecosystem services from these resources has increased dramatically in recent years. Producers and land managers in the western U.S. are faced with information gaps regarding plant community restoration and establishment of desired species, management of grazing livestock, and vegetation responses to management actions in spatially and temporally variable environments. Filling these information gaps is critical to maintaining the security of livestock forage across the western U.S. During the next five years we will build on our prior research addressing issues critical to our understanding and management of sagebrush steppe rangeland. Our focus will be on 1) developing management practices and tools for restoring/rehabilitating sagebrush steppe following weed invasion and juniper expansion, and 2) developing management guidelines, literature syntheses, decision support tools, and assessment systems for conserving intact plant communities in a variable environment. Strong emphasis will be placed on operationalizing these products through our existing outreach program and strengthening outreach through direct support of parallel efforts by Oregon State University. To maximize benefit to a diversity of customers, outreach will target and support numerous regional collaborative management groups. Although the problem areas addressed by the Burns location stem from local and regional scale issues, our specific research questions and designs help to illuminate principles applicable to national and international issues and audiences through peer review research and synthesis publications. A focus of this research unit has been to provide tools that managers can use, including but not limited to non-technical research reports, information syntheses, field guides and decision trees. Projected benefits of successfully completing and transferring this research are: 1) improved management of existing sagebrush steppe for a variety of uses including forage production and habitat for critical wildlife species, 2) increased probability of success for restoration/revegetation projects, 3) increased ability to determine the effects of management practices within complex landscapes, and 4) a better understanding of the role of climate and site factors in influencing site productivity and restoration/revegetation success.
3. Progress Report:
This is a bridging project with the project currently undergoing National Program 215 Office of Scientific Quality review and is a continuation of the expired project 2070-21630-001-00D. For Objective 1, ARS scientists in Burns, Oregon, determined that grazing by cattle in the spring or the fall before the wildfire season could be used to greatly reduce the likelihood of wildfire. This was accomplished by reducing the probability that an ignition source would ignite fuel and if fuel was ignited that the fire would spread. Though both grazing treatments greatly reduced the probability of initial fire spread compared to ungrazed areas, spring grazing was more effective than fall grazing. ARS scientist in Burns, Oregon, also determined that light to moderate stocking rates, using deferred rotation, are applicable to sustainable grazing of sagebrush steppe rangelands. Grazing had no impact to forbs typically consumed by sage-grouse, a species that has been considered for listing under the Endangered Species Act (ESA). Deferred-rotation grazing systems are frequently recommended by federal land management agencies and practiced by livestock operators. For Objective 2, ARS scientists in Burns, Oregon, completed analysis of a study comparing 30-year post-treatment successional dynamics of cut versus burned juniper woodlands. Analysis revealed significant management-related differences between treatments. Specifically, cutting (compared to fire) missed small trees resulting in more rapid return of juniper; e.g., with cutting, juniper returned to conditions that would preclude habitat occupancy by sage-grouse in less than 30 years compared to an estimated 100+ years for fire. Conversely, sagebrush was unaffected by cutting but required several decades for recovery in burned areas. Manuscripts are being prepared for peer review publication. ARS scientists in Burns, Oregon, provided data for use in refining and testing new vegetation mapping technology with collaborators at the University of Montana. This effort has produced a system that utilizes Google Earth Engine and satellite imagery to map both current and retroactive (back to 1984) vegetation composition and abundance and has a wide variety of management applications. A peer review paper based on this work is in journal review. ARS scientists in Burns, Oregon, completed cooperative research with U.S. Fish and Wildlife Service (USFWS) and other partners to determine the efficacy of using threat-based state and transition models to predict sage-grouse habitat occupancy. These models, previously developed by ARS scientists and collaborators, are currently being used to help guide vegetation management on over five million acres of public and private rangelands in Oregon. Results of this research indicate that sage-grouse predictably occupy states in high ecological condition. This data serves to justify unification of rangeland management and sage-grouse habitat management goals, greatly simplifying management planning and implementation. Data analysis is complete and a peer review manuscript is in process. For Objective 3, ARS scientists in Burns, Oregon, initiated research to determine if externally-applied abscisic acid (ABA) can be used to delay germination of fall-planted native bunchgrasses until after danger of winter frozen soil conditions has passed. Burns ARS scientists determined that juniper woodland control is needed to restore long-term forage production and biodiversity. ARS scientists determined that burning was more effective than mechanical treatments for controlling juniper at extended time horizons and they are finalizing data analysis and two peer review manuscripts are in process.
1. Threat-based management of sugarbrush rangeland. When declines in populations of sensitive wildlife species such as sage-grouse interface with ecosystem problems, the historical inertia of species-centric management can elevate short-term wildlife concerns over long-term ecosystem management priorities and create barriers for agricultural commodity production on public rangelands. Scientists in Burns, Oregon, in partnership with Oregon State University and The Nature Conservancy, have developed an ecological threat-based management framework that can be used to help ameliorate threats to both commodity production and wildlife habitat on sagebrush rangeland, including exotic annual grass invasion and expansion of native conifer populations. These models merge the needs of critical wildlife species with ecosystem management imperatives using State-and-Transition theory and are currently being used to guide management on over six million acres of private, State, and Federal rangeland in Oregon. At customer request, the researchers recently developed a publication entitled, "Threat-Based Land Management in the Northern Great Basin: A Field Guide." This product presents straightforward and pictorially-guided instructions for state delineation and field use of threat-based models. Since its printing in February of 2018, the researchers have put over 1,000 copies of this document into the hands of interested customers, have held training sessions and workshops scheduled for land managers in Oregon and Idaho, are discussing applications of these materials with private and public land managers in Nevada, and are cooperatively discussing the use of threat-based models as the basis of a carbon mitigation system for the State of Oregon.
Bates, J.D., Davies, K.W. 2018. Quaking aspen woodland after conifer control: tree and shrub dynamics. Forest Ecology and Management. 409:233-240. https://doi.org/10.1016/j.foreco.2017.11.019.
Davies, K.W., Bates, J.D., Hulet, A. 2017. Attempting to restore mountain big sagebrush (Artemisia tridentata ssp. vaseyana) four years after fire. Restoration Ecology. 25(5):717-722. https://doi.org/10.1111/rec.12505.
Davies, K.W., Boyd, C.S., Bates, J.D., Gearhart, A.L. 2017. Legacy microsite effect on the survival of bitterbrush outplantings after prescribed fire: capitalizing on spatial variability to improve restoration. Restoration Ecology. 25(5):723-730. https://doi.org/10.1111/rec.12506.
Davies, K.W., Boyd, C.S., Bates, J.D. 2018. Eighty years of grazing by cattle modifies sagebrush and bunchgrass structure. Rangeland Ecology and Management. 71(3):275-280. https://doi.org/10.1016/j.rama.2018.01.002.
Davies, K.W., Boyd, C.S., Madsen, M.D., Kerby, J., Hulet, A. 2018. Evaluating a seed technology for sagebrush restoration across an elevation gradient: support for bet hedging. Rangeland Ecology and Management. 71(1):19-24. https://doi.org/10.1016/j.rama.2017.07.006.
Davies, K.W., Boyd, C.S. 2018. Longer-term evaluation of revegetation of medusahead-invaded sagebrush steppe. Rangeland Ecology and Management. 71(3):292-297. https://doi.org/10.1016/j.rama.2018.02.001.
Davies, K.W., Johnson, D.D. 2017. Established perennial vegetation provides high resistance to reinvasion by exotic annual grasses. Rangeland Ecology and Management. 70(6):748-754. https://doi.org/10.1016/j.rama.2017.06.001.
Davies, K.W. 2018. Incorporating seeds in activated carbon pellets limits herbicide effects to seeded bunchgrasses when controlling exotic annuals. Rangeland Ecology and Management. 71(3):323-326. https://doi.org/10.1016/j.rama.2017.12.010.
Fulbright, T.E., Davies, K.W., Archer, S.R. 2018. Wildlife responses to brush management: a contemporary evaluation. Rangeland Ecology and Management. 71(1):35-44. https://doi.org/10.1016/j.rama.2017.07.001.
Denton, E.M., Smith, B.S., Hamerlynck, E.P., Sheley, R.L. 2018. Seedling defoliation and drought stress: variation in intensity and frequency affect performance and survival. Rangeland Ecology and Management. 71(1):25-34. https://doi.org/10.1016/j.rama.2017.06.014.
Dale, V.H., Denton, E.M. 2018. Plant succession on the Mount St. Helens debris-avalanche deposit and the role of non-native species. In: Crisafulli, C., Dale, V., editors. Ecological Responses at Mount St. Helens: Revisited 35 years after the 1980 Eruption. New York, NY: Springer. p. 149-164.
Griffin-Nolan, R.J., Carroll, C.J., Denton, E.M., Johnston, M.K., Collins, S.L., Smith, M.D., Knapp, A.K. 2018. Legacy effects of a regional drought on aboveground net primary production in six central US grasslands. Plant Ecology. 219(5):505-515. https://doi.org/10.1007/s11258-018-0813-7.
Bates, J.D., Davies, K.W. 2017. Effects of conifer treatments on soil nutrient availability and plant composition in sagebrush steppe. Forest Ecology and Management. 400:631-644.
Boyd, C.S., Davies, K.W., Collins, G.H. 2017. Impacts of feral horse use on herbaceous riparian vegetation within a sagebrush steppe ecosystem. Rangeland Ecology and Management. 70(4):411-417. https://doi.org/10.1016/j.rama.2017.02.001.
Boyd, C.S., Davies, K.W., Lemos, J.A. 2017. The influence of soil color on seedbed microclimate and seedling demographics of a perennial bunchgrass. Rangeland Ecology and Management. 70(5):621-624. https://doi.org/10.1016/j.rama.2017.03.004.
Barron-Gafford, G., Sanchez-Cohen, E., Minor, R., Hyendryz, S., Lee, E., Sutter, L., Tran, N., Parra, E., Colella, T., Murphy, P., Hamerlynck, E.P., Kumar, P., Scott, R.L. 2017. Impacts of hydraulic redistribution on grass-tree competition versus facilitation in a semiarid savanna. New Phytologist. 215(4):1451-1461. https://doi.org/10.1111/nph.14693.
Hardegree, S.P., Moffet, C., Walters, C.T., Sheley, R.L., Flerchinger, G.N. 2017. Hydrothermal germination models: Improving experimental efficiency by limiting data collection to the relevant hydrothermal range. Crop Science. 57(5):2753-2760. doi:10.2135/cropsci2017.02.0133.