After a day’s delay due to high winds, the National Park Service launched its second controlled burn in two years at Gettysburg National Military Park. Fire specialists from nearby states and a special National Park Service Fire Crew from Delaware Water Gap National Recreation Area conducted the burn, which lit off at about 10 AM. South and East Confederate Avenues were closed all day to all traffic, including foot, and bicycle, out of prudent safety concerns. Little Round top and for a while, Devil’s Den were also closed.
Note: Click on photographs to enlarge them.
Note: Photographs were taken from South Confederate Avenue at the entrance to the Bushman Farm Lane.
The fire crews began in the Triangular Field on the west side of Houck’s Ridge [behind Devil’s Den].
The science behind the controlled burn is complex, demanding detailed geographic and geological decisions, and prevailing winds, even as they change. The fire crews set a line of fire where they wanted the fire to stop, a narrow stretch, and they made use of existing fire breaks such as driveways, and roads. Once the stop line was made, the crews would light the start line and let the wind do the work of pushing the fires toward the stop lines. You can see this demonstrated in the images below.
First one of the the stop lines is created – follow the smoke. Then, as you can see, the left margin of the burn area is burned to maintain the fire in the field. Here the crew is spreading the fire down the Slyder Farm Lane to start the burn. While they are doing that, another crew is creating the stop line just viewable as the smoke at the edge of the woods:
That is how it is done.There is, of course, much more to it, but the field north of the Slyder Farm Lane is a great example of how it is done.
However, once you start the fire to clear the underbrush in the wooded areas, you must be careful not to allow the trees themselves to burn. At the end of this burn there were two trees afire just below Devil’s Den. As of 8 PM they were still burning, closely attended by the fire crews.
W. G. Davis
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