As much as 70 percent of California's $1 billion orange crop has been destroyed by record cold temperatures across the state, officials and farmers said yesterday.

It will take days to make a full assessment of the losses. But the state's top agriculture official said that damage appears to be greater and more widespread than in the freeze of 1998, which destroyed $700 million worth of produce across California.

"This cold incident will surpass the 1998-99 freeze," said A.G. Kawamura, Secretary of the California Department of Food and Agriculture.

Losses, while greatest in the San Joaquin Valley, seem to be spread throughout many parts of the state typically immune to freezes, he said, "from San Diego, to the Central Valley, to the coast."

In addition to citrus fruits, growers are reporting damage to leafy greens, avocados, strawberries and blueberries, said Kawamura, who has spent the past few days visiting farms from Fresno to Ventura.

Some farmers are reporting 100 percent damage to their crops, and many others say well over half their produce is destroyed, he added.

Consumers could feel the impact in price at the grocery store, said Toni Spigelmyer, spokeswoman for Sysco Corp., the largest U.S. food-service distributor.

"We've lost about 50 percent of the orange crops, had significant losses on lemons, and it's going to have an effect on vegetables," Spigelmyer said. "Basically, what we're going to see is a tighter supply and much higher prices."

The cold snap is particularly insidious because it has lasted twice as long as normal winter blasts and plunged temperatures below 25 degrees, essentially making night warming efforts by farmers futile.

"The trees are looking sad," said Joel Nelsen, president of California Citrus Mutual, a growers association. "They're normally a vibrant green color with these bright orange dots all over them. Now the leaves are curling, and they're turning yellow. They're really stressed."

Citrus farming employs 12,500 people in California, not including those who pack the fruit and drive the delivery trucks. Even the companies that make the boxes in which the fruit is shipped will have a bad year, he said.

Claire Smith, spokeswoman for the 6,000-member Sunkist Growers cooperative, said that up to 70 percent of the navel oranges still on its members' California trees have been damaged. That amounts to about half of the state's overall navel crop and would be worth about $500 million. It remains unclear whether the trees are damaged, something that could cause problems next season.

As the state recorded another morning of record lows yesterday, farmers worked to assess the damage, hopeful that rising temperatures predicted for today will help preserve the crops that have survived.

"We will be lucky to salvage a quarter to a third of what was left. It is a bleak situation," said Charles Sheldon, who had picked less than a third of his 900-acre citrus orchard near Lindsay when temperatures plunged. Yesterday he started juicing a portion of the crop too damaged to sell as fresh fruit.

Avocado farmers say this past weekend was the most damaging in 16 years, since the Big Freeze of 1990 wiped out crops.

Guy Witney, of the California Avocado Commission, said the frost could not have come at a worse time for avocado farmers.

Only 5 percent of the $350-million crop was picked before this weekend, Witney said, meaning that most of the fruit was still on the trees and vulnerable to the cold.