Combined with exacerbated drought conditions, increased frequency and severity of wildfires can suppress tree regeneration both from slower tree recruitment and growth rates, and enhanced post-disturbance woody shrub sprouting. It is estimated that with warmer climates, increased drought, and more frequent and severe fires, almost one-third of the Klamath forest setting could transition from a conifer-dominated forest to a shrub-dominated chaparral ecosystem. Thus, understanding how early-successional shrubs (Ceanothus spp.) and the dominant conifer species (Douglas fir) interact in post-fire environments is crucial to accurately predict the future dynamics of the Klamath.

We specifically address the following questions: How do Ceanothus and Douglas-fir biomass vary along gradients of time since fire and climatic water deficit? How do soil resources (soil C and N) vary along gradients of time since fire and climatic water deficit? Does the biological nitrogen fixation capacity of Ceanothus increase soil N levels, and if so, is this influence reflected in Douglas-fir biomass? Does competition from Ceanothus affect early-successional Douglas-fir biomass?

This work has been published in Forests in 2021 and can be reached below: