Harnessing Mycorrhizal Fungi to Improve Post-fire Restoration and Forestry
How do wildfires change the underground world that young trees depend on? We have several projects investigating how fire changes soils and impacts the success of regenerating or replanted seedlings. In our first study, led by then-undergraduate-researcher, now-PhD-student Dustin Lower, we conducted a greenhouse experiment to test how soils from burned and unburned forests affect the growth of Douglas-fir seedlings and their partnerships with beneficial fungi. We found that high-severity burn soils were depleted of beneficial fungi, leading to reduced root colonization and stunted seedling growth. In contrast, soils from low-severity burns retained rich, diverse fungal communities that supported healthier seedlings, similar to those grown in unburned soils. These findings highlight the powerful role of underground fungal communities in post-fire forest recovery and point to the potential of microbial restoration to help forests bounce back after severe wildfires.
Dustin is now expanding on this work through a CAL FIRE graduate research award focused on how soil inoculation and nursery treatments can improve seedling outplanting success for reforestation after stand-replacing fires. Through his work, we will develop valuable tools for forest restoration and post-fire recovery in vulnerable forests across California.
