My current research focuses on providing the National Forest System with the science foundation for a National Reforestation Strategy and the Lassen and Modoc National Forests with the science foundation to revise their forest plans. I am leading an international team to better understand the long-term process of tree root system architecture in response to nursery practices and on-going mechanical stresses. I continue work with using biochar to improve nursery efficiencies. And, I am working to understand carbon and nitrogen pools under different land management and silviculture scenarios.
I am also Director the Western Center for Native Plant Conservation and Restoration Science, a collaboration of scientists in the Pacific Northwest, Pacific Southwest, and Rocky Mountain Research Stations working in these fields.
My research interests include all aspects of propagating and outplanting native plants. From the nursery perspective, my research includes nursery production systems, specifically propagation, plant-disease interactions, plant nutrition, and water management. From the outplanting perspective, my research includes assisted migration as a management adaptation to climate change, functional restoration of plant communities, and long-term development of tree root systems.
View my video profile: https://www.youtube.com/watch?v=KZ3w60gcoBo&list=PLNsZX2SBTlVmV1MpNisJ4NdNpsV9Hulrj&index=20
My research has improved the process of native plant propagation. Native plant species are produced with my protocols and my protocol format is routinely followed in the literature and the Native Plant Propagation Protocol Database. My seminal work on quantifying errant discharge of water and nutrients using novel techniques I developed led to science-based options to apply water and fertilizer more efficiently and sustainably. Basic research on nursery root diseases and the subsequent best management plans that my teams developed significantly reduced incidence of this serious pathogen. We found that the fungus Fusarium commune, rather than Fusarium oxysporum, is the more virulent pathogen, supplanting existing concepts about this nursery disease. Our development of a rapid molecular assay to discern this disease has markedly changed the paradigm of future research endeavors concerning this nursery pathogen, and has potential to revolutionize disease assessment in nurseries by providing real-time information. My teams have developed and advocated methods to avoid or mitigate pitfalls of confounding factors in nursery research and in deploying stocktype trials. I synthesized and delivered my research, along with that of peer scientists, and subsequently provided nursery managers and field restorationists holistic tools; some tools have been translated into Spanish, Dari, Creole, French, and Arabic. To improve communication within the native plant propagation profession, my Internet-based propagation protocol database, and the 3150 native plant propagation protocols in it, was accessed 12,675 times during 2019. I led efforts to bridge the gap between native plant propagation and native plant deployment by initiating a new journal that is innovative because it publishes refereed research and general technical articles to encourage “cross pollination” among researchers and field professionals. Recent work showing on-going changes to coarse root system architecture challenges existing tree-stability paradigms and provides new conceptual models. I co-led the WO-requested effort to synthesize the science underpinning contemporary approaches to forest restoration, including native plant deployment, and argue for approaching forest restoration (and other ecosystems as well), from a functional standpoint. Team work with assisted migration challenges existing paradigms about appropriate plant material transfer guidelines, lays the groundwork for future research in assisted migration, and in concert with functional restoration, is contributing significantly to, and expanding the debate about, restoration practices in response to changes in climate.
In the US, more than 1400 native plant nurseries, operated by federal, tribal, state, private, and not-for-profit entitiies, annually produce more than a billion seedlings for reforestation and restoration. Ensuring seedlings are produced efficiently and with high quality reduces costs and improves seedling performance (survival and growth) after outplanting. The end result is that restoration work to maintain ecosystem function is done in the most efficient and economic ways possible. In addition, my research with assisted migration and functional restoration will help ensure that appropriate plant materials, in terms of adaptation, are applied to the landscape.