Submitted to: Rangeland Ecology and Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/11/2012
Publication Date: 5/1/2012
Publication URL: http://naldc.nal.usda.gov.d2.nal.usda.gov/catalog/54351
Citation: Madsen, M.D., Kostka, S.J., Inouye, A., Zvirzdin, D.L. 2012. Postfire restoration of soil hydrology and wildland vegetation using surfactant seed coating technology. Rangeland Ecology and Management. 65(3):253-259. Interpretive Summary: In an effort to restore ecosystem services, land managers commonly reseed rangeland areas that have been impacted by catastrophic wildfires. Unfortunately, these reseeding efforts often experience poor seedling establishment. The development or enhancement of a water repellent layer within the soil profile has been linked with reseeding failure. Non-ionic soil surfactants (wetting agents) can be effective in ameliorating soil water repellency; however, their application in wildland ecosystems has been logistically and economically prohibitive. In this study we evaluated an economical and innovative solution for applying soil surfactants using seed coating technology. Laboratory results indicated that surfactant seed coating (SSC) technology increased the amount of moisture in the soil by improving infiltration and moisture retention. Evaluations in the greenhouse demonstrated that SSC technology dramatically improved plant survival and biomass production. Future research is needed to confirm these findings in the field, to determine if this technology should be recommended as a post-fire restoration treatment.
Technical Abstract: n semi-arid environments, soil water repellency can contribute to reseeding failure by reducing soil moisture availability and site stability. Non-ionic soil surfactants (wetting agents) have been shown to be effective in ameliorating soil water repellency; however, their application in wildland ecosystems can be logistically and economically prohibitive. In this study we evaluated an economical and innovative solution for applying soil surfactants using seed coating technology. The objectives of this research were to 1) establish the efficacy of a surfactant seed coating (SSC) in ameliorating soil water repellency, and 2) determine the influence of SSC on seedling emergence and plant survival. To accomplish the first objective, detailed soil column experiments were conducted in the laboratory on water repellent soil obtained from a burned pinyon-juniper woodland. Upon the same soil, the second objective was met through greenhouse testing of SSC on crested wheatgrass and bluebunch wheatgrass seed. Results indicate that SSC increased soil infiltration, percolation, and moisture retention. This technology had no influence on seedling emergence for crested wheatgrass, but SSC improved bluebunch wheatgrass emergence threefold. Plant survival was dramatically improved by the SSC. At the conclusion of the study, the majority of the emerged non-coated seeds had desiccated, while 37 % of the plants survived in the SSC treatment. Overall, these results indicate that it may be plausible for SSC(s) to improve post-fire reseeding success. Future research is needed to confirm these findings in the field to determine if SSC technology should be recommended as a post-fire restoration treatment.