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Prescribed burning

Prescribed burning (or controlled burning) is used to reduce hazardous fuel loads that may accumulate, restore/improve natural systems, alter vegetative communities, improve wildlife and livestock habitat, control pests, and improve access. A prescribed fire is one that is applied knowingly to vegetative fuels of a specific area and under specific weather conditions to accomplish a specific objective. Prescribed burning is a common management practice of ecosystems that historically experienced frequent fire return intervals.

The time-lapse video above and picture below shows prescribed burns conducted at Fort Keogh Livestock & Range Research Laboratory that are part of research projects. The areas to be burned are surrounded by a fire break (dirt road, mowed area, or recently disked pasture). This is essentially a strip of ground with little to no fuel for the fire to spread across. The crews start a back fire (fire that burns against the prevailing wind) using a drip torch to establish a "black line" that provides an additional buffer to prevent the fire from escaping containment. Both groups start from a common anchor point from a down wind location of the unit to be burned. A support crew, with fire fighting equipment, follows maintaining the line, and ready to put out any spot fires to avoid starting a wildfire (fire outside of fire/black line).

The video shows the creation of parallel fires (inset is group to the right). Eventually the loop is closed creating a perimeter fire which had a relatively small and well contained head fire. Head fires are the most dangerous because they burn in the direction of the prevailing wind. The most intense flames visible in this sequence occur from a section of perimeter fire that is behaving somewhat like a head fire.

To the right- This is a separate fire. This crew is burning a small plot. Since the wind is blowing to the right, the person with the drip torch is creating a head fire. The person to the left with the hose is creating a "wet line" to prevent the fire from backing against the wind and moving to the left.

This video sequence was taken using a Canon Digital Rebel controlled by a TC-80N3. This footage was shot at an interval of approximately one frame every 10 seconds or 20 seconds (second sequence). I actually assisted on the fire crews while the camera was on autopilot.