LOS ANGELES (AP) — With nearly 30,000 acres charred already, California could be in for a severe wildfire season, U.S. Sen. Dianne Feinstein said Thursday as firefighters worked to contain blazes around the state.

Feinstein cited the increase in brush spawned by the winter’s heavy rains and the recent severe heat wave that dried out vegetation.

“Making matters worse, six years of drought has left us with more than 100 million dead trees,” she said in a statement. “This overabundance of fuel, combined with fires that are burning hotter and faster, has created a potentially catastrophic scenario in California that poses an increased risk not only to property but also the brave men and women fighting these fires.”

California has so far not had the type of infernos that have destroyed hundreds or thousands of homes in the past, but fires have been occurring from the Oregon border to San Diego County.

Most have been in wildlands but some have occurred dangerously close to homes, including two blazes among hillside residences in the Los Angeles area on Wednesday.

Active new blazes include a 760-acre (307-hectare) wildfire burning on the Camp Pendleton Marine Corps base in San Diego County and in neighboring brushlands of San Clemente, and a 630-acre (255-hectare) blaze on the Mariposa County foothills of the western Sierra Nevada.

The Pendleton fire resulted in a smoke alert from regional air quality regulators as it spread a strong odor across Orange and Los Angeles counties early in the day, but it was 70 percent contained by late afternoon.

A new blaze in the Malibu area that broke out Thursday afternoon also threatened homes, but firefighters quickly stopped its progress.

The state’s biggest current fire was 90 percent contained after burning across nearly 10 square miles (26 sq. kilometers) in Riverside County, about 80 miles (128.7 kilometers) east of Los Angeles. Crews remained on the scene to complete the containment line and patrol the burn scar.

On the Central Coast, crews were also wrapping up a 2.5-square-mile (6.5-sq. kilometer) fire in rural San Luis Obispo County.

The state has had more fires and more acreage burned so far this year than the same time last year even though the latter was part of the drought, said Scott McLean, spokesman for the California Department of Forestry and Fire Protection.

The majority of the burned acreage has been grasses that grew as remarkable precipitation ended the epic dry spell.

Stands of tall grasses are “very dense and susceptible to any spark,” McLean said.

There have also been some timber fires at higher elevations and authorities are concerned about the estimated 102 million trees that succumbed to the drought and insect infestations.

“These are large swaths of trees that are dead, since 2010,” McLean said. “Trees are just falling down.”