Live fuel moisture is important for assessing fire danger. LFM is defined as the percentage of water content to dry matter content in live vegetation.
The direct measurement of LFM is done by collecting fresh field samples of chamise, drying them until all moisture is evaporated, and calculating the water content difference between fresh and dry samples.
Chamise is one of the most common shrub species found in Southern California chaparral communities. Chamise is evergreen, but it is sensitive to seasonal drought.
During Southern California’s long dry season, chamise leaf moisture content drops as soil water availability declines. In extreme conditions, rapid dry down can happen in days, for example during Santa Ana winds affecting Southern California.
Field-sampled LFM are gathered at five locations throughout Santa Barbara County. They include Tepesquet, Harris Grade, Cachuma, Refugio and West Gaviota.
Current Santa Barbara County average live fuel moisture level is at 64 percent; 60 percent is considered critical. Declining live fuel moisture may reach a threshold that increases susceptibility to large wildfires.
The Santa Barbara County Fire Department urges people to use caution in the coming months.
— Capt. David Sadecki is a public information officer for the Santa Barbara County Fire Department.