OROVILLE — Authorities say the Wall Fire burning near Oroville has destroyed at least 41 homes.
The numbers released Tuesday come after fire crews surveyed the destruction of the blaze burning in the grassy foothills of the Sierra Nevada, about 60 miles north of Sacramento.
The California Department of Forestry and Fire Protection says at least 4,000 people are under evacuation orders. Some residents have returned home.
The blaze has burned nearly 9 square miles since it broke out Friday afternoon, and was 45 percent contained by Tuesday morning. The cause of the fire remains under investigation.
Wildfires Get Help From Unlikely Source: the Rain
Major winter downpours that pulled the state out of years of drought also brought a layer of grass that early-summer fires are greedily feeding on.
"What the heavy rains have done is created a grass crop that we haven't seen in forever," said Santa Barbara County fire Capt. Dave Zaniboni, whose department was also battling two large wildfires. "That creates faster-moving fires, hotter fires, it carries fire much more readily."
Older, dried-out trees and vegetation are especially dangerous for wildland blazes, but enough new and drying grass can provide links between such tinderboxes.
Bennet Milloy of the California Department of Forestry and Fire Protection says that diseased and damaged trees and dead vegetation from during the drought "can be ignited by the lighter fuels that come from the wet winter," making for better-fed fires.
Chuck Wilsey returned to his ranch home in Oroville on Monday after evacuating over the weekend, relieved to learn it had been spared by the wildfire, just as he had stayed clear of troubles brought on by a damaged spillway at Oroville Dam five months ago.
"I don't know what's worse — fire or water — it's a toss-up," Wilsey, 53, said after returning to his home.
His daughter, Krystle Chambers, who lives on the same property, said the one-two punch of floods and fires was taking its toll.
"It's hard, it's rough," she said. "Way too many hits. First it's this side of town, then the other side of town. It almost makes you want to move."
Wilsey was already making new plans in case the fire makes another run at them. He said he was leaving his trailer attached to his truck and telling his daughters to keep prized possessions they couldn't take the first time close at hand.
The larger of the two, the Alamo Fire, charred more than 45 square miles of dry brush and has burned 20 structures since it broke out. It was 45 percent contained.
To the south the 17-square-mile Whittier Fire is 25 percent contained. It broke out near a campsite and sent hundreds of campers scrambling, including about 90 children and 50 staff members at the Circle V Ranch who had to take shelter until they could be safely evacuated.
Crews were getting a break from rising humidity and light winds.