Thick Brush in Hills Heightens Fire Danger for Holiday Weekend : Fourth of July: Winter’s torrential rains have contributed to the present hazard of dry grass that could easily be set ablaze by errant fireworks.

Heavy rains that helped ease drought conditions earlier this year have resulted in a lush growth of brush and grass on hillsides surrounding the San Fernando Valley, increasing the already high fire danger normally associated with the Fourth of July holiday, authorities said Thursday.

Los Angeles County Fire Capt. Donald A. Pierpont said that the late winter torrential rains have created a summer hazard as the rich growth of brush dries out.

“We have a tremendous grass crop caused by the high rainfall earlier this year,” said Pierpont, the Fire Department’s vegetation management coordinator. “We have more and taller grass than we have had in certainly the last five years. It’s all dried out now and ready to burn.”

Added to the dry condition of the brush is the traditional danger presented by errant fireworks. Although Palmdale is the only city in the north county where fireworks are legally sold, both county and Los Angeles city fire officials said that the Fourth of July holiday each year brings numerous calls as a result of fireworks being illegally used.

“The Fourth is traditionally our busiest day,” Los Angeles Fire Battalion Chief Greg West said. “The majority of the calls are fireworks related--fires and injuries related to fireworks.”

West said his department is expecting 2,000 calls for service on July 4--double the normal daily number. To prepare for that, he said, staffing has been increased for the weekend, water and hose trucks will be stationed in brush areas and a helicopter will patrol the city full time.

In the Valley, the dirt road section of Mulholland Drive between Encino Hills Drive and Canoga Avenue will be closed because the area has been popular with users of illegal fireworks in the past, West said.

“We have a tremendous amount of hillside areas in the city and the large amount of rain we had has made the grass grow more,” West said. “It’s all dried out and we call it flash fuel because it is so easily and quickly ignited. That is particularly where the danger is this year. Fireworks in these areas will lead to a major hillside brush fire.”

County Fire Capt. Steve Valenzuela said staffing has been increased in his department during the weekend as well. The county’s emergency coordination center will remain in operation through the weekend to better coordinate and speed response to any fires, he added.

“The Fourth of July is traditionally the busiest time of the year,” Valenzuela said. “We always have our emergency response teams prepared to go.”

Forecasts for the weekend are for temperatures in the 90s with low humidity. Pierpont said the moisture levels in brush samples taken throughout the county have been steadily dropping to levels where brush is known to burn quickly and easily.

The county takes biweekly moisture measurements from live brush at 18 locations in the county. The samples are weighed and then dried in an oven and weighed again to determine how much moisture they had been holding. Pierpont said a plant can hold up to twice its weight in moisture, meaning a moisture level of 180% to 200% is considered optimum because the material is slow to burn.

When moisture levels in the brush samples drop to 60% to 90%, the material is considered critically dry. Pierpont said the most recent sampling of brush put moisture levels in the mountains in the north county at 90%.

“We are right at that break point,” Pierpont said. “You add the fireworks ignition component and it makes this a bad weekend for us. The potential for fire from fireworks is really high.”