Birch, Berries, And The Boreal Forest: Activities And Impacts Of Harvesting Non-Timber Forest Products In Interior Alaska

Abstract

Harvesting wild berries, firewood, and other non-timber forest products (NTFPs) from the boreal forest in Interior Alaska is a common activity amongst local residents. NTFPs are harvested for personal use, subsistence, and commercial purposes. While these activities contribute to informal household economies and livelihoods, harvest of NTFPs are not well documented in Alaska. Availability of these ecosystem services may be altered under changing management and climate regimes. This interdisciplinary dissertation takes a look at the activities and impacts of current NTFP harvesting practices. Survey results from a forest use survey provide insight into harvest activity in the Tanana Valley. Wild blueberries (38.5% of households with mean harvested amount of 7.7 quarts) and firewood (25.0% of households with a mean harvest amount of 4.7 cords) were reported harvested with greatest frequency, and harvesting activities were mostly concentrated around larger population centers. Interviews were conducted with personal use and subsistence NTFP harvesters from Interior Alaska. Participants enjoy harvesting from the forest, and that the importance of harvesting is a combination of both the intangible benefits from the activity and the tangible harvested items. Harvested NTFPs were seen as high-quality products that were otherwise unavailable or inaccessible. Birch syrup is a commercially available NTFP produced in Alaska by a small number of companies. Similar to maple syrup, producing birch syrup is a labor intensive process with marginal profits. Interviews were conducted with workers in the Alaskan birch syrup industry, who reported that they were seeking an alternative to the traditional employment. The effects from mechanical damage from tapping for spring sap on birch's vigor are of concern to birch syrup producers and natural resource managers. This study compared the annual increment growth of Alaskan birch trees, Betula neoalaskana, between tapped and untapped trees. No significant difference was detected from tapping, but annual variability in growth was strongly significant. A temperature index accounted for nearly two-thirds of the annual variability. Pairing this index with two climate scenarios, birch growth was extended out through the 21st century. As temperatures rise, birch in Interior Alaska are projected to face a critical threshold, which may limit or extinguish their ability to sustain growth and yield a sustainable sap resource. Integrating the survey, interview, and dendroclimatological data provides a richer picture of how NTFP harvesters actively use the forest and about the benefits derived. These findings can assist resource managers in balancing these needs with those of other forest uses on public land.