Maintaining California Black Oak (Quercus kelloggii) Woodlands with Cultural Fire in Karuk and Yurok Territories in Northwest California

Keywords: Cultural fire, Indigenous peoples, California, Black oak, Pyrogeography
Session Type: Virtual Paper Abstract
Day: Tuesday
Session Start / End Time: 3/1/2022 09:40 AM (Eastern Time (US & Canada)) - 3/1/2022 11:00 AM (Eastern Time (US & Canada))
Room: Virtual 20

Abstract

Cultural fires enhance the abundance and quality of species and habitats fundamental to Indigenous culture in California. Historically, Indigenous peoples repeatedly burned the understories of California black oak (Quercus kelloggii) woodlands to improve the gathering efficiency of acorns and other understory species. In northwest California, the Karuk and Yurok Tribes are revitalizing cultural burns, in part to maintain black oak and other hardwood species that, in the absence of burning, have been encroached by Douglas fir (Pseudotsuga menziesii). I used field surveys and an analysis of deciduous tree cover from remotely sensed images to evaluate overstory species composition, stand basal area (>10 cm dbh), and tree densities within high frequency cultural burn sites (3 or more burns from 1989 – 2019), in comparison to adjacent unburned sites, and sites where cultural burns have been recently re-introduced (low frequency sites: <3 burn events from 1989 – 2019). The data shows that high frequency burn events facilitate hardwood tree overstories predominantly composed of deciduous black oak, and that at low frequency burn sites Douglas fir dominates the overstory (p < 0.001). Overstory tree basal area at sites dominated by Douglas fir are 1.85-fold greater than at sites dominated by hardwoods (p < 0.001), and tree densities are 1.5-fold greater at low frequency burn sites compared with high frequency burn sites (p < 0.01). High frequency, low-intensity cultural burning is an effective means to maintain black oak woodlands that supports ecological heterogeneity, reduces wildfire risks, and enhances Indigenous livelihoods.