Pre-emptive and high input restoration
There is general agreement that re-establishment of healthy, diverse native plant communities in rangelands of the western U.S. can provide resistance to invasion by undesirable species, but restoration efforts often fail. We are investigating two inter-related approaches to improving restoration success, neither of which is the status quo for land management agencies in the West: 1) targeting restoration efforts before an area has crossed a virtually irreversible ecological threshold and 2) using higher-input, more labor-intensive approaches than are the standard practice. In a project funded by USDA-AFRI, we are researching both the ecological and institutional feasibility of these approaches across different soil moisture-temperature regimes in the Great Basin. We are testing how to restore native herbaceous species in areas where sagebrush canopies are intact (i.e., prior to conversion from sagebrush shrubland to cheatgrass monoculture), as well as planting seedlings (rather than seeding). In a second project funded by the BLM, we are targeting a salt desert shrub area in southern Idaho that would typically be either be viewed as a ‘throwaway’ area or restored with non-native species. We are testing various high-input restoration methods to restoring native species, such as hand-planting, micro-site-specific planting, and targeted herbicide treatments. Finally, in a project near Soda Springs, Idaho, we are testing the efficacy of concentrating restoration efforts into the establishment of ‘restoration islands’ (rather than more diffusely across the landscape) to restore sagebrush communities for sage-grouse habitat. |
Integrating large herbivores into restoration
Although large herbivores (e.g., cattle) are implicitly involved in most rangeland restoration projects, they usually are not explicitly included as part of the restoration process. More closely examining the roles of the wild and domestic large herbivores that are supported by these rangeland systems provides opportunities to both mitigate herbivory as a barrier to restoration success and use large herbivores as tools for restoration. Current research efforts include: 1) a Utah DWR-funded project in which we are using a combination of field experiments and digital soil mapping to identify areas in the Colorado Plateau where wild ungulates are least likely to limit establishment and persistence of sagebrush; 2) field experiments at multiple sites across the Great Basin testing how different periods of rest from livestock grazing (e.g., 2 vs. 3 years) following fire affects tiller demography of native bunchgrasses in sagebrush steppe; and 3) field tests of how large ungulates can be used as restoration tools, in particular elk for enhancing the herbaceous understory in northern Utah; cattle for controlling Phragmites in wetlands of the Great Salt Lake; and cattle for reducing bare ground and creating wildlife hotspots in Kenya. |
Grazing ecology and livestock-wildlife-plant interactions
Wild and domestic herbivores share many of the world’s rangelands and can profoundly influence the landscapes that support them. Gaps in our understanding of their effects and how to most effectively manage them include: 1) the relative effects of wild vs. domestic large herbivores on their habitat, and 2) how the relationships among different large herbivores and their habitats vary according to ecological context (e.g., soil type, plant community, productivity). Some of the lab’s research on this topic takes place in the Kenya Long-term Exclosure Experiment (KLEE), a broad-scale replicated experiment that, within a single ecosystem, tests the separate and combined effects of cattle, meso-herbivore wildlife, and mega-herbivore wildlife. Other lab research is based in Utah and the Great Basin, where we are using long-term livestock and wild ungulate exclosures to better understand relationships among elk, deer and cattle and their habitat, as well as how those ecological relationships are mediated by factors such as climate and plant community context. This work will provide insight into the fundamental context-dependent relationships among large ungulate species, but will also inform applied rangeland management and our ability to anticipate the ecosystem effects of herbivory. |
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Other interests and past projects
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