Tree planting for global change adaptation: lessons from “early adopters” in the Northeastern US

Written by Peter Clark and Tony D’Amato – University of Vermont

Natural resource managers are tasked with stewarding ecosystems in the context of the complex challenges of global climate change. Given their key role, it is important to understand how or why management decisions are made and to understand the barriers and opportunities for management. Among various tactics used by foresters, tree planting has increasingly been proposed as a tool to address the challenges of global change (referred to here as “adaptation plantings”). Historically, foresters in the Northeast seldom relied on tree planting because, unlike other regions in North America, these forests have a propensity to naturally regenerate ecologically and economically desirable species. Yet, adaptation plantings have been proposed to restore culturally and ecologically important keystone species or ecosystems, diversify composition to promote resilience, mitigate greenhouse gas emissions, and adapt forests to a warming climate via assisted migration.

Due in part to the novelty of some of these practices, information is lacking on how foresters are engaged with adaptation plantings. To better understand this, a team of researchers surveyed managers to assess perspectives, applications, and barriers associated with tree planting for adaptation in the Northeast. This team was led by Drs. Peter Clark and Tony D’Amato from the University of Vermont, along with collaborators from the USDA Forest Service, the Northern Institute for Applied Climate Science (NIACS), and the University of Minnesota. The team specifically focused on a population of “early adopters” because, as has been demonstrated in other fields, the perspectives of early adopters of a practice can serve as an important litmus test to understand and refine the state of the art for subsequent users.

Findings from this work highlight that motivations for adaptation plantings differ, but generally trend towards planting to adapt to future conditions. Furthermore, respondents show a growing interest in and application of adaptation plantings, specifically the use of forested assisted migration among a suite of species. Assisted migration is a concept that has been more recently applied as a forest management tool given the recognition that the rate of climate warming far outpaces the ability of plants to naturally migrate by an order of magnitude, particularly long-lived perennials like trees. Yet, when it comes to assisted migration, the devil is in the details. Foresters in this study acting as early adopters report greater comfort with and application of some types of assisted migration like the movement of southern, climate-adapted seed sources of native species (“assisted population expansion”) or even modest northward movement of species found nearby along their range margins (“assisted range expansion”). Contrastingly, most survey respondents indicate discomfort with the notion of translocation of climate exotic species or the long-distance movement of plants that never would realistically migrate to sites over long time periods (“assisted species migration”). These nuances among the three types of assisted migration are important to distinguish, and foresters in the study apparently grasp these differences. Many respondents attribute these trends to increased awareness, acceptance, and interest in the practice.

Although this work points to growing momentum of the use of adaptation plantings to meet diverse needs in an era of global change, respondents still report many key barriers for successful planting efforts associated with biotic and abiotic (i.e., vegetative competition, browse), information and material (i.e., seedling availability in nurseries), and policy, social, and economic factors (i.e., funding). Taken together, this work points to a growing interest in and application of adaptation plantings among early adopters in the region, which may serve to refine the practice if/when this tactic becomes more widely used among natural resource managers.

Read the full study here: https://www.frontiersin.org/journals/forests-and-global-change/articles/10.3389/ffgc.2024.1386211/full

Clark et al. 2024. Forest assisted migration and adaptation plantings in the Northeastern US: perspectives and applications from early adopters. Frontiers in Forest and Global Change

For additional background, see the featured article on page 6 of the spring 2023 edition of Forest Steward magazine: “Assisting Tree Migration to Adapt to Climate” by Brian Palik.