Casas Arroyo Fire Prevention and Protection Plan

Fire Facts

1. The most common initiator of fires in this region is lightning, and the most common time of the year for lightning-caused fires is in the mid-to-late summer monsoon. Because of fire suppression and fire-fighting practices, Casas Arroyo may have missed from 8 to 20 naturally-occurring fires in the last 100 years, allowing dead, flammable materials to build up to abnormally high quantities.
2. A grass fire on the Audubon Society Research Ranch Preserve May 6, 1987 top-killed approximately 25% of all oaks in the area of the fire. Of these, nearly half of the trees did not resprout (did not grow back from the roots). The topography, plant communities, and amount of fuel on the research ranch site are similar to that of Casas Arroyo.
3. Additional fire danger may be incurred at any time of the year from cigarettes thrown out of cars on the highways (or on the property), and by careless handling of fire sources (such as children playing with matches, improper storage of flammables, burning of trash, etc., sparks flying from unprotected chimneys, incorrect processing of fireplace embers).
4. Fire increases in intensity (heat), and speed of travel as the following factors increase:
   1. dryness of the air (lowered humidity)
   2. wind speed (increased oxygen to fire)
   3. upslope of the land (even a very small slope may increase the speed and heat of the fire tremendously)
   4. amount of fuel, especially fine fuels (dry grasses and leaves) and highly volatile fuels (juniper and cliff rose)
5. The only factor (from above) that can reasonably be modified is the amount and location of the fuel.
6. Compacted fuels (matted vegetation, leaves, animal droppings) do not burn quickly, but may smolder for long periods of time.
7. Dry grasses burn much more quickly than trees because of their large surface areas; the oldest trees that do not have a great deal of debris and small branches on the ground at their bases may be immune to an average grass fire that has not been driven into the crowns of trees. Juniper and cliffrose is more volatile and will burn more quickly than oak brush.
8. Wildlife, except for some rodents and insects, are usually able to escape to protected ground from a wildfire, unless the fire is of unusual extent, or is wind- driven at a high rate of speed.