Thumbs Up or Down to Annual Burning of a Tidal Marsh in Maryland?
Date of this Version
Fire Science Brief, Issue 134, May 2011
Currently land managers at Blackwater National Wildlife Refuge on the Eastern Shore of Maryland annually burn most of the marsh as a way to enhance wildlife habitat, promote habitat for rare and threatened plant species, and avoid hazardous buildups of fuel. However, it was unclear how this regimen affects the elevation of the marsh and marsh sustainability. This research attempted to answer those questions, which are critical in light of expected future sea-level rise. The method used allowed the scientists to measure marsh surface accretion (building) and elevation trends, and to determine the separate infl uence of surface and subsurface processes on marsh elevation change. Annual burning proved to have a less negative effect on factors infl uencing marsh vertical development than did no burning, a 3–5 year burn cycle, or a 7–10 year burn cycle. The scientists caution that these results are not transferable to other places because of the unique hydrology of the area. They note that in the adjacent state-owned marsh, the results would likely be vastly different. They also note that this is a short-term study covering only three fire seasons and two growing seasons, and that the long-term results of the longer burn cycles will not be clear for another 30 years or so.