Oak Woodlands

Oak woodlands provide important habitat for a variety of species and support a range of ecosystem services. They are an indicator of habitat availability for oak-dependent species such as the Acorn Woodpecker (Melanerpes formicivorus) as well as for a range of predator and prey species. This important habitat faces numerous threats, among them, fire regimes with increased intensities and frequencies, infestation by the goldspotted oak borer (Agrilus auroguttatus), and drought. While some of these threats (e.g., the goldspotted oak borer) can be (and are being) managed, the need for ongoing management and monitoring remains.

This assessment looked at three metrics: sapling presence, percentage of living trees, and canopy cover of individual trees. Oak woodlands in the Coastal Study Area are faring slightly better than those in the Central Study Area, with the former having a higher number of saplings and live trees as well as at least 25% canopy cover. Coastal oak woodlands are in a state of caution for two of the three metrics and good for the third, while the Central Study Area oak woodlands are in a state of significant concern for one metric and caution for the remaining two. However, oak woodlands in both the Coastal and Central Study Areas are in a state of caution with a decreasing trend, an assessment in which there is a low level of confidence due to a lack of repeated or long-term data collection.

The assessment includes a number of recommendations, but two important data gaps  that could inform management and restoration strategies were identified. First, oak woodland age structure, which indicates age-class diversity and also highlights bottlenecks (e.g., seed germination and seedling and sapling survival). Second, identification of locations with higher genetic diversity and a prevalence of useful genes, which could be important in maintaining genetic diversity and preserving the species’ evolutionary potential, particularly in the face of climate change.