Landowner functional types to characterize response to invasive forest insects

Abstract

Invasive forest insects can induce tree mortality in two ways: (a) by directly harming trees; or (b) by influencing forest owners to pre‐emptively harvest threatened trees. This study investigates forest owners’ intentions to harvest trees threatened by invasive insects. Our first objective is to identify and characterize agent functional types (AFTs) of family forest owners in the northeastern United States using a set of contingent behaviour questions contained in a mail survey. We establish AFTs as a form of dimension reduction, effectively casting landowners into a typology in which each type (AFT) has distinct probabilities of tree harvesting in response to forest insects. Our analysis identifies three functional types of landowners: ‘Cutters’ (46% of respondents; high intent to harvest trees impacted by invasive forest insects), ‘Responsive Cutters’ (42% of respondents; intent sensitive to insect impact severity), and ‘Non‐cutters’ (12% of respondents; low intent to cut). Our second objective is to model AFT membership to predict the distribution of AFTs across the landscape. Predictors are chosen from a set of survey, geographic and demographic features. Our best AFT‐prediction model has three predictor variables: parcel size (hectares of forest), geographical region, and town‐level forested fraction. Application of the model provides a high‐resolution probability distribution of AFTs across the landscape. By coupling human and insect behaviour, our results allow for holistic assessments of how invasive forest insects disturb forests, inclusive of the management response to these pests. A free Plain Language Summary can be found within the Supporting Information of this article.

Emerald ash borer intensifies harvest regimes on private land

“…In the context of this study, “ash species” includes white ash ( Fraxinus americana ), green ash ( Fraxinus pennsylvanica ), and black ash ( Fraxinus nigra ). We considered privately owned plots only (omitting federal and state plots) to contextualize our findings within the discussion of private landowner behavior (e.g., Holt et al, 2020; MacLean et al, 2020; Markowski‐Lindsay et al, 2020).…”

Logging response alters trajectories of reorganization after loss of a foundation tree species

“…Some insects cause changes in forest type by eliminating specific tree species (Lovett et al, 2016). Human responses to insect outbreaks may amplify their effects, as many landowners choose to harvest forests threatened by insects (Foster & Orwig, 2006; Holt et al, 2020). Logging may result in larger changes to forest structure and composition, and greater aboveground carbon loss than insect damage alone, as timber harvests result in more abrupt mortality, remove large logs rather than leaving dead trees on‐site, remove additional nonhost tree species, and can cause disturbance to the forest floor (MacLean et al, 2020; Markowski‐Lindsay et al, 2020).…”

U.S. Family Forest Owners' Forest Management for Climate Adaptation: Perspectives From Extension and Outreach Specialists

“…There have been numerous attempts to understand management behavior and decades of interventions trying to influence family forest owners (Silver et al, 2015;Thompson et al, 2017). Several studies argue that family forest owners should be divided into typologies based on their reasons for owning land and behavioral responses (Majumdar et al, 2008;Goyke et al, 2019;Holt et al, 2020). In terms of specific management predictions, Thompson et al (2017) found that the largest predictors of harvesting behavior among family forest owners in the Northeastern US were not related to the characteristics of landowners themselves, but rather geographical factors such as distance to roads or biological factors such as basal area and forest type.…”