Agriculture Reference
In-Depth Information
N
Riverside County
Orange
County
Temecula
Oceanside
Legend
Cities
Counties
San Diego
County
Mean Fire Freq. Departure 2006
- 998 - -81
-80- -51
San Diego
-50- -21
-20- -1
0
1-19
20-49
50-89
0
5
10
20
30
40
Kilometers
Fig. 5.10
Fire departure map for the Cleveland National Forest in southern California, USA.
Negative indices indicate an excess of fires during the past century higher than historical levels
and are typical of the lower foothills dominated by chaparral, sage scrub and grassland. Positive
indices indicate missed fire cycles and are in higher elevation coniferous forests. (Data from
Hugh Safford, U.S. Forest Service, 2008.)
how to reduce the vulnerability of communities to wildfire risk and manage
natural resources for sustainability.
Because much of this landscape burns at a frequency greater than historical
levels (
Fig. 5.10
), excess fires are a major resource concern in much of the current
chaparral landscape. Many species in these shrublands are extirpated when fire
