Location: Range and Meadow Forage Management Research2021 Annual Report
The first and primary research goal of this project is to improve our systems approach to restoration for annual grass management in the sagebrush steppe of North America. In 2013, we provided a systems approach that advances ecological restoration beyond conceptual and phenomenological descriptions to quantitative process-based models that can be used to address specific applied questions (James et al. 2013a). Our systems approach uses life histories to identify transitions important to seedling establishment and maturation. It links those transitions to ecological processes directing establishment and management practices that can favorably impact those processes. Our technology transfer goal is to use the research results for developing tools aimed at assisting land managers in selecting seeds based on their quality, guidelines for determining when and what species to broadcast during restoration, and guidelines on assessing and managing defoliation of newly emerged seedlings at risk to herbivory. Specifically, during the next five years we will focus on the following objectives: Objective 1: Enhance rangeland restoration processes by improving the establishment of seedlings of desirable plant species (such as increasing seed quality and seedling survival), acquiring and implementing basic knowledge to match naturally occurring physical safe-sites with seed traits, identifying and quantifying the effects of herbivory on seedling survivorship, and developing threshold guidelines for mitigation. Sub-objective 1A: Improve rangeland restoration success by enhancing seed quality and emergence survival of desired restoration species and develop simple seed quality selection criteria. Sub-objective 1B: Develop the basic knowledge to match naturally occurring physical safesites with seed traits to maximize seedling establishment during restoration. Sub-objective 1C: Identify and quantify the effects of herbivory on seedling survivorship to develop threshold guidelines for mitigation during restoration. Objective 2: Integrate research into an ecological systems approach to restoration with current cost/benefit models and link to site-specific best management practices. Sub-objective 2A: Develop decision-support tools for 1) choosing seeds based on quality characteristics, 2) matching seed size, number, and physical safe-site availability during restoration, and 3) identifying and managing risk to seedlings associated with herbivory. Sub-objective 2B: Inform and update our systems approach to include important aspects of seed quality, maximizing physical safe-site capture, and minimizing seedlings risk of herbivory and link this model with existing cost/benefit models.
Rangelands cover nearly one-half of the earths land surface and provide life sustaining goods and services to about one-third of the global population. Low and variable rainfall combined with often infertile soil make the world’s rangelands highly susceptible to degradation, invasion, and global climate change (Millennium Ecosystem Assessment 2005). The inability to establish healthy plant communities is cited by stakeholders as the single largest barrier to implementing restoration and turning the tide against the hundreds of thousands of hectares of sagebrush steppe lost to invasive plants each year. Despite over a century of research, rangeland science lacks a comprehensive understanding of the ecological processes influencing seedling establishment. The goal of this project is to improve restoration for annual grass management in the sagebrush steppe of North America. Using a series of field and laboratory tests, our first study attempts to improve rangeland restoration success by enhancing seed quality and emergence survival of desired restoration species and develop simple seed quality selection criteria. Our second study is aimed at developing the basic knowledge to match naturally occurring physical safe-sites with seed traits to maximize seedling establishment during restoration. Third, we plan to identify and quantify the effects of herbivory on seedling survivorship to develop threshold guidelines for successful restoration. Finally, we will integrate this research into an ecological systems approach to restoration with current cost/benefit models. Strong emphasis will be placed on operationalizing research knowledge and 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.
This is the final report for bridging project 2070-22000-006-00D, "A Systems Approach to Restoring Invaded Sagebrush Steppe," which has been replaced by the new in-house project, 2070-22000-007-00D. For Sub-objective 1A, two manuscripts about enhancing seed quality to improve seedling emergence survival of desired restoration species and developing simple seed quality selection criteria have been drafted and are in in-house review. Sub-objectives 2 A and 2B are well-underway, but COVID-19 and inability to meet with the cooperators and user groups have slowed progress substantially. For Sub-objective 1B, a manuscript describing the pattern of safe site formation and how it varies in space and time in the Northern Great Basin is in preparation aiming for a submission date of July 2021. This information will allow us to make inferences about how these safe sites will affect seeding success. These hypotheses can then be tested with the data we collected as part of this experiment. These findings will be reported in our follow-up manuscript. For Sub-objective 1C, final sampling was conducted on the large multisite experiment looking at natural herbivory on perennial grass restorations across the Northern Great Basin over the course of five years. These data were summarized in an initial analysis for presentation at the 2020 conference for the Society for Range Management. A paper was accepted for publication by AoB Plants detailing the findings of our previous work looking at how seedlings of common perennial grass species used in restoration responded to controlled defoliation varying in intensity and frequency.
Barron-Gafford, G.A., Knowles, J.F., Perez Sanchez-Canete, E., Minor, R.L., Lee, E., Sutter, L., Tran, N., Murphy, P., Hamerlynck, E.P., Kumar, P., Scott, R.L. 2020. Hydraulic redistribution buffers climate variability and regulates grass-tree interactions in a semiarid riparian savanna. Ecohydrology. 14(3). Article e2271. https://doi.org/10.1002/eco.2271.
Hamerlynck, E.P., O'Connor, R.C. 2021. An assessment of seed head and flag leaf contributions to reproductive effort in sagebrush steppe bunchgrasses. Journal of Arid Environments. 187. Article 104442. https://doi.org/10.1016/j.jaridenv.2021.104442.
Davies, K.W., Bates, J.D., Boyd, C.S. 2020. Response of planted sagebrush seedlings to cattle grazing applied to decrease fire probability. Rangeland Ecology and Management. 73(5):629-635. https://doi.org/10.1016/j.rama.2020.05.002.
Bates, J.D., Boyd, C.S., Davies, K.W. 2020. Longer-term post-fire succession on Wyoming big sagebrush steppe. International Journal of Wildland Fire. 29(3):229-239. https://doi.org/10.1071/WF19109.
Copeland, S.M., Baughman, O.W., Boyd, C.S., Davies, K.W., Kerby, J., Kildisheva, O., Svejcar, T. 2021. Improving restoration success through a precision restoration framework. Restoration Ecology. 29(2). Article e13348. https://doi.org/10.1111/rec.13348.
Holfus, C.M., Rios, R.C., Boyd, C.S., Mata-Gonzalez, R. 2021. Preemergent herbicide protection seed coating: A promising new restoration tool. Rangeland Ecology and Management. 76:95-99. https://doi.org/10.1016/j.rama.2021.02.005.