Drip torches are used to ignite the fire front. They consist of a 5-quart-capacity fuel reservoir, a valve to control flow, and a tube to deliver fuel to the igniter. The igniter serves as a continuous flame to ignite drops of fuel which fall to the herbaceous vegetation as the drip torch is tilted toward the ground. Torches are also available that are pressured, carried as backpack units, or mounted on ATVs.
Drip torches use a mixture of diesel fuel and gasoline to supply a steady stream of ignited fuel. A ratio of 70% diesel to 30% gasoline is a rule-of-thumb for warm weather and a 60:40 ratio is recommended for cool weather. The higher the air temperature the less gasoline is needed. To be safe, it is advisable to use the minimum amount of gasoline for proper operation.