Mimicking Fire for Successful Chaparral Restoration

Abstract Following disturbance, seed pre-treatment is essential for re-establishing many species with low germination rates. However, some seeds, such as those from chaparral plants, do not respond to common horticultural treatments. Instead, methods that mimic chaparral's natural succession cues (e.g., fire) should be used to improve seed germination and restoration success. Fire effects, such as heat, charate, leachate, smoke, and/or liquid smoke, are effective in breaking long-term seed dormancy in many chaparral plants. The challenge is to break seed dormancy in a cost- and time-efficient manner that can be used in large-scale restoration projects. Results of our study show that short-term exposure (10 minutes to one hour) to liquid smoke and/or heat enhances seed germination of Adenostoma fasciculatum Hook. & Arn. (chamise), Ceanothus cuneatus (Hook.) Nutt. (buckbrush), and Salvia mellifera Greene (black sage). Chamise seeds treated with liquid smoke have the greatest percent increase of seed germina...