Informing reforestation with the Experimental Network for Assisted Migration and Establishment Silviculture (ENAMES)

Abstract

Recent climate and disturbance conditions in Western U.S. forests have led to significant reforestation needs, necessitating the development of climate-informed management strategies. Promising adaptation strategies include assisted population migration, the movement of seed sources or populations to new locations within the historical species range, combined with silvicultural establishment practices that can improve short-term seedling survival and longer term stand resilience to future climate. Presently, there are challenges to the operational use of assisted population migration and uncertainty regarding its success when combined with the effects of various silvicultural practices and seed transfer guidelines. We established the Experimental Network for Assisted Migration and Establishment Silviculture (ENAMES) to evaluate the short- and long-term success of operationally implemented reforestation treatments that incorporate assisted population migration and silvicultural establishment practices using a network of sites selected through science-management partnerships with federal, state, and tribal ownerships. Here, we document the context underlying ENAMES, describe the experimental network and its establishment, share lessons learned, and describe future opportunities for the network. The network consists of 37 sites from northern Washington to central California, including a wide range of pre-disturbance forest types and climatic conditions. The practitioner partner at each site selected planted species and silvicultural practices to ensure management relevance. The most common species planted were Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa), while the most common silvicultural treatments were comparisons of stock types or vegetation control methods. Planting of sites was initiated in 2021 and is expected to be completed in 2026. Comparisons of survival and growth by treatment are a key outcome of this study, with initial measurements planned for 1-year post-planting, and every 5 years thereafter. We anticipate that ENAMES will clarify uncertainties regarding assisted population migration and that planting sites will be used as demonstrations to showcase treatment effects. ENAMES provides a powerful opportunity to test the efficacy of assisted population migration and silvicultural establishment treatments, while using a science-management partnership model to ensure that practices are operationally relevant.

Citation

Agne, Michelle C.; Slesak, Robert A.; Gonzalez Mantecon, Laura; Wright, Jessica W.; Kolpak, Scott E.; Baumgart, Erin E.; Bower, Andrew D.; Darbyshire, Robyn; Ellwanger, Claire; Erickson, Vicky J.; Ferreria, Arnaldo R.; Looney, Christopher E.; Roskilly, Beth A.; Sherlock, Joseph W. 2025. Informing reforestation with the Experimental Network for Assisted Migration and Establishment Silviculture (ENAMES). Gen Tech. Rep. PNW-GTR-1031. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 103 p. https://doi.org/10.2737/pnw-gtr-1031.