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Prescribed fires can be ignited by many different techniques.You should ask yourself several questions before determining which technique is the most appropriate for a specific burn unit. First, will the technique allow for your specific goals or objectives to be achieved? Second, is it the safest method for burning that unit; and third, is it the safest technique for the crew and people around the burn unit? If the answer to any of these questions is “no,” you should reevaluate the burn plan and use a different ignition technique that will allow you to safely achieve your goals. Ignition Hazards When igniting a prescribed fire, be aware of several hazards that usually occur along the edge of the burn unit while the fires are being lit and can cause the fire to escape the unit. First, watch for changes in the wind’s speed or direction when you are burning; this is a common problem on any prescribed burn. Because wind speed and direction are usually not constant, the fire boss should be ready for a 45° shift in the winds on any burn; for example, if the wind is out of the southwest, you could very well expect winds to vary from the west to south. Most of all, know the weather conditions in the area where you are burning. Entrapment of personnel is always a concern when igniting a fire (Figure 13-1). Make sure everyone completely understands the ignition plan. Have personnel watch out for the people directly in front of and behind them. Make sure all personnel are out of the burn unit unless they are lighting the fire. There may be a need to stop every so often and have everyone check in before proceeding with the burn. These precautions can help keep personnel from becoming trapped or injured within the burn unit. Spotting, or spotfires, is another problem to watch out for. Spotfires can be caused by volatile fuels burning along the fire line (Bunting and Wright 1974; Weir 2007), heavy amounts of fine herbaceous fuels right on the line, fire or smoke whirls, hardwood leaves, or a variety of other problems (Wright and Bailey 1982; Weir 2007). Many of these spotfire causes can be managed by reducing the amount or type of fuel right next to the line or burning under the proper weather conditions (Weir 2007). Slopes along the fireline can cause some potentially hazardous problems. Fire travels faster upslope, and the slope effect can override the wind direction (Pyne 1984). A fire burning up a 20° slope will burn four times faster than the chapter 13 Ignition Techniques And call ye on the name of your gods, and I will call on the name of the Lord: and the God that answereth by fire, let him be God. And all the people answered and said, It is well spoken. —I Kings 18:24 Ignition Techniques 137 same fire on level ground (Cheney and Sullivan 1997), so remember to be extra careful when burning on uphill slopes. The person igniting the fire and the suppression crew following the igniter may not be able to keep up with the fire. In this case the fire may race up the slope with an increased flame height and intensity, causing spotting, or the fire may even jump the firebreak. Probably the safest way to handle this situation is to stop igniting well before the foot of the slope so the fire will not back or carry up the slope. Then send a person to the top of the slope to ignite the fire back down the slope and tie in where ignition stopped. This fire should be less intense and easier to manage. Heavy fuels can cause many problems along the fireline. An option for reducing your risk is to reduce the amount of fuel. This can be achieved by mechanical means such as mowing, shredding, chipping, mulching, or dozing. It can also be accomplished biologically through the use of herbicides or with grazing animals. Whichever method you use, make sure that it does not create more fuel or cause the fuels to increase in combustibility. Another potential problem when backfiring a burn unit is incomplete burnout of blacklines caused by nonflammable, sparse, or irregular fuels, as well as breaks in those fuels such as livestock trails, pasture roads, rock outcroppings, or skips in the ignition pattern.To avoid incomplete burnouts, have the personnel following behind watch for areas that have not burned and...

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