Notes on Prescribed Fire
Sources:

Pyne, S.J., P.L. Andrews, and R.D. Laven 1996. Introduction to wildland fire 2^nd Ed. John Wiley and Sons Inc. 769 pp.

1. Difference between wild and prescribed fires is cultural not natural.

1. the differences have nothing to do with the physical or biological properties of fire
2. a prescribed fire promotes the general land management goals of the responsible agency or party whereas, wildfire does not.
3. wildfire occurs under conditions that make fire control difficult and lead to net resource damage, whereas prescribed fire can be set (or let burn) under conditions that favor control and that lead, on the whole, to net enhancement of the resource or ecosystem.

1. Every prescribed fire must be executed under the provisions of a prescribed fire plan
   1. the essence of the plan is the prescription
      1. prescription is analogous to a fire behavior forecast around which plans for control of the fire are made.
      2. prescription is the set of conditions within which a prescribed fire will be allowed to occur.
2. Fire techniques Table
3. Aspects of fires that can be controlled
   1. size
      1. nature of the burn (as defined by its fuels), purposes of burn, prospects for control, and cost will usually be determining factors
      2. exception is prescribed natural fire where size is determined by fire management area and fire is allowed within limits to set its own size
   2. intensity
      1. achieved through prescription, fuel preparations, and choice of ignition patterns.
      2. fire effects vary with intensity and fire intensity is rarely uniform across entire fire.
   3. timing
      1. diurnal and seasonal timing affects fire behavior while season of firing affects biological consequences of the burn.
   4. frequency
      1. how often fires occur.
      2. single episode of burning or a periodic application of fire
      3. control over frequency of fires affects fire intensity, and fire size
   5. classification
      1. the ability to classify a fire as a wildfire or prescribed fire
      2. criteria for such classification are not the properties of the fire but rather the cultural values of the management agency.
4. Prescribed fire plans include
5. Selected goals or objectives for prescribed burning
   1. slash burning -
      1. common in northern Rockies. Has 2 purposes:
         1. prepare forested sites for replanting
         2. reduce fuel loads for better fire protection
   2. pre-suppression burning -
      1. e.g., in California chaparral
         1. creating and maintenance of chaparral fuel breaks
         2. patch burning within fuel break blocks to reduce fuels and promote biodiversity
         3. purpose is to reduce risks of wildfires and costly damage to adjacent urbanized areas.
   3. underburning -
      1. Southeastern U.S. pine forests -
         1. broadcast burning for fuel reduction and silvicultural improvement.
         2. retarding successional stage to early stages favored by fire dependent species
      2. Arizona pine forests -
         1. to restore ponderosa forests (drastically changed by removal of fire through suppression over the last 75 years) to something like their historic fire regime (5-20 yrs)
         2. to change community structure to more natural state
   4. ecosystem maintenance -
      1. southern Florida wetlands (yes wetlands can burn)
         1. purpose is to perpetuate natural vegetation and communities
         2. it is the interaction of fire and water that created and maintain the sawgrass communities of the Everglades.
   5. prescribed natural fire
      1. Idaho wilderness -
         1. control over several fire variables (timing, ignition, and fuels preparation) is minimal
         2. prescriptions must be broad based
         3. variability of the burn with its variable outcomes is part of the desired condition
   6. Type conversion
      1. western rangelands
         1. purposes:
            1. sustain grasslands
            2. restore sites over run by woody species to something like their former grassland communities.