Improving Reseeding Success after Catastrophic Wildfire with Surfactant Seed Coating Technology

摘要

The application of soil surfactants in wildfire-affected ecosystems has been limited due to logistical and economic constraints associated with the standard practice of using large quantities of irrigation water as the surfactant carrier. We tested a potential solution to this problem that uses seed coating technology to harness the seed as the carrier. Through this approach, precipitation leaches the surfactant from the seed into the soil where it absorbs onto the soil particles and ameliorates water repellency within the seeds microsite. We evaluated this technology in a burned, highly water repellent, pinon-juniper woodland. Within a randomized complete block design, we separately seeded two bunchgrass species (Indian ricegrass and crested wheatgrass), whose seeds was either left uncoated or coated with a surfactant blend of alkylpolyglycoside and ethylene oxide/propylene oxide block copolymer. Plots were monitored through two growing seasons. In the spring after seeding, plant density and cover in the surfactant coated treatments were approximately 3-fold higher than the uncoated treatments. Two years after seeding, differences in plant density between the treatments decreased slightly, with the surfactant coated treatments having 2.8-fold higher density, as compared to the uncoated treatments. Over this same period, relative differences in cover between the treatments had increased, with surfactant coated treatments having 3.4-fold higher cover than the uncoated treatments. Overall, the results of this study demonstrate the ability of surfactant seed coating technology to improve seedling emergence and establishment. Future research is merited for evaluating the technology at larger-scales and within different ecosystems.