Mapping burn severity with before/after 30m LANDSAT imagery is a useful tool in characterizing large wildfires in forested areas. Post-fire imagery used in classification is usually acquired 1-2 growing seasons post-burn to allow for delayed tree mortality. While useful for measuring the loss of forested resources, how effective is this at describing effects on herbaceous understory components?  In 2011, the Rockhouse fire burned over 300,000 acres of Chihuahuan desert, including much of the Davis Mountains. Two years post-fire, we field sampled 12 sites in the Davis Mountains, using a burn severity map following Monitoring Trends in Burn Severity methodology to set up burn severity “treatments†consisting of unburned, light, moderate, and severe. Sites were blocked on 3 NRCS SSURGO soil descriptions, giving a total of 12 sites sampled. Variables sampled included ground cover (perennial grass, rock, litter, and bare ground), species richness by functional group, standing crop, one-hour litter accumulation, and plant density. Data were analyzed in a randomized block design, using ANOVA and Fisher's LSD. We detected few differences between the various severity levels. Bare ground was the only ground cover variable significantly different (p = 0.0492). Litter accumulation also varied between severity levels (p=0.0218), while total standing crop did not (p=0.6921). Total and functional group species richness did not differ between treatments. Differences in plant functional density were not apparent as well. Our analysis 2-years post fire indicates that further exploration may be required in order to effectively characterize wildfire effects on understory vegetation through remote sensing.
Oral presentation and poster titles, abstracts, and authors from the Society for Range Management (SRM) Annual Meetings and Tradeshows, from 2013 forward.