Locally harvested wood at a sawmill in New Hampshire, United States. Photo by David Foster.

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Invasive tree insects pose a threat to many forests, particularly in the Northeastern United States, where both the insects and host tree species are abundant. Tree insects threaten forests in two main ways: 1) by physically damaging trees; and 2) by influencing landowners to harvest (cut) trees before they are completely damaged by the insects. In this study, we investigate family forest owners’ intentions to harvest their trees in response to the recent or future arrival of invasive tree insects on their land. Many landowners in the Northeastern United States are familiar with invasive tree insects, and there is a legacy of insects inducing tree-harvesting. For example, American landowners harvested hemlock trees in response to the hemlock woolly adelgid in the 1980s and 1990s, compounding the disturbance of the insects themselves. Despite the historical relationships between landowners, insects and trees, the patterns of landowner response to tree insects are not well-characterized.

Using results of a mail survey, we developed a landowner typology that simplifies forest owner behaviour into a few different “functional types” based on their stated contingent behaviour. We identified three main types of landowner: “Cutters” (high intent to harvest trees impacted by invasive forest insects), “Responsive Cutters” (moderate intent to harvest), and “Non-cutters” (low intent to harvest). We then characterized these types with respect to their land-owning objectives, management history, and socio-demographic attributes. For example, “non-cutters” are about twice as likely to be female, compared to the other two types. We also developed a predictive model that projects our typology across New England based on location, amount of forest in the town, and size of the landowner’s parcel. This predictive model allows us to calculate probabilities of harvesting behaviour under various invasive insect scenarios. Given that over eighty percent of survey respondents indicated that they would consider harvesting in response to insects, it is crucial to characterize this potentially widespread disturbance.  

Firewood harvested on private land in Maine, Unite States. Photo by Rob Lilieholm.