Today I had the opportunity to present at the SER-Cal Conference (Society for Ecological Restoration – California) some of my research crossing summer watering/grass flushing with burning to control annual grass cover in restored perennial grasslands in the Central Valley of California. Here you can find the abstract (below), and a PDF version of the presentation as well as the conference booklet for downloading.
Summer watering and fire to control weeds in restored grasslands. Kristina Wolf* and Truman P. Young.
Department of Plant Sciences, Mail Stop 1, University of California, Davis, 95616; email@example.com.
California’s native grasslands have been largely replaced by exotic annual grasses. Management of invasive annual grasses is important to reduce weed seedbanks and competitive pressure, and increase perennial grass success. Previous experiments revealed that summer watering treatments, no matter how intensive, did not produce long-term results in terms of percent cover of weedy annual plants in the following growing season. I tested combinations of summer watering and fire at a restored Central Valley grassland, now heavily invaded by non-native annual grasses. Across six replicates, I applied five summer watering treatments of different frequencies, timing, and amounts (and a control of no water) in August 2012 in an attempt to ‘flush’ the exotic seed bank. This was followed shortly thereafter by fire, which top-killed all plants on the site. Both annual and perennial grasses germinated or resumed growth within one week after the fire. I monitored exotic grass seedling emergence and native perennial grass growth weekly through December following the fire, and annual and perennial cover at peak flowering after commencement of natural rains, to determine if combinations of watering and fire reduced annual grass cover short-term, and in the subsequent growing season. Final results for all treatments will be presented, and compared with previous parallel watering-only experiments.