Montaña de Oro is a California State Park located not far from the Cal Poly Campus. This park is typical of many, in that it contains plant communities adapted to fire, but it is also adjacent to developed areas where people live. Prescribed burning in the park is therefore a difficult and potentially dangerous undertaking. Some plant species in Montaña de Oro are actually dependent on fire for regeneration, similar to many found in California's shrublands. One such shrub, known as "Morro manzanita" (Arctostaphylos morroensis), is an endangered species and found only in the immediate vacinity of Montaña de Oro.

To gain a better understanding of how fire should be used in the management of Morro manzanita, a prescribed burn was performed in a small portion of the plant's current distribution. Claudia Tyler (Institute for Computational Earth Systems Science, UCSB) and Dennis Odion (Marine Science Institute, UCSB) were the PI's on this project. I participated in the pre- and post-burn sampling, as well as monitoring during the fire. Our main goal was to determine which factors prior to the fire (e.g., species composition and fuel loading) and during the fire (e.g., fire intensity and fuel consumption) relate most strongly to successful regeneration. Click here to see the approximate location of this fire, which was ~10 acres in size.

Almost none of the Morro manzanita shrubs survived in areas that actually burned. Regeneration of Morro manzanita has also been extremely low, far below that needed for long-term persistence of this species. The possible causes for the lack of regeneration (e.g., low fire intensity and/or not enough time since the last fire to build up sufficient seedbank) are still under consideration. However, one of the clear lessons of this project is that successful prescribed burning may be more complex than we assume for plant species that are adapted to fire at relatively specific fire intervals or intensities. Prescribed fires can result in local extirpation of important native species, even when their persistence is the main management goal. Follow this link to the abstract of the report for this project. Some related photos are included below.

In many prescribed fires, a road or some other feature on the landscape is useful for keeping the fire in check. Here we see fire-fighting personel monitoring the perimeter for "spotting," or spreading to start new fires via airborn embers.

The fire generally stopped spreading where fuel was not continuous. However, flame lengths were in excess of 50 ft in some of the thicker stands of brush (note the height of the person in lower right of this figure).

In much of the study area, the fire consumed mostly fine fuels (leaves, twigs, and litter). As a surrogate measure for fire intensity, we set out cans with a pre-measured amount of water in them. Cans were later retrieved, and the amount of water boiled off was recorded.