LOS ANGELES, Jan 13 (Reuters) - California's lucrative citrus harvest has dodged significant damage so far despite the latest round of plunging temperatures on Sunday brought on by an Arctic air mass, farmers said.
Tom Blakely, spokesman for grower trade association California Citrus Mutual, said that while weekend temperatures had been the coldest of the winter, they had not dipped into the low 20s Fahrenheit (minus 5-6 Celsius) as forecast last week.
Temperatures that low, if sustained, pose a serious threat to California's $2 billion-a-year citrus industry, which accounts for most of the oranges and lemons commercially available to U.S. consumers.
"Up until now, the forecasts with the temperatures that they have been predicting have not been realized," Blakely said. "We've seen temperatures bottoming out more in the mid 20s, about 25F (minus 3.8C) for a short period of time. That's the lowest that we've seen in the commercial growing areas.
"And with frost protection measures that the growers employ ... combined with the wind machines and good inversion layers, mixing the air above, they've been able to keep the temperatures in the groves out of the critical zone," he said.
Farmers have spent a few "long nights" protecting their crops and remain concerned about Sunday night and Monday, Blakely said. A warming trend was expected on Tuesday.
"We've still got at least one more night, and maybe two more nights, to go through. But we've gotten through the last three nights minus a lot of sleep but otherwise in pretty good shape," he said.
California's strawberries, valued at roughly $2.2 billion a year, are especially vulnerable to cold snaps, with plants generally unable to withstand temperatures lower than 34F (1.1C) for extended periods of time, said Carolyn O'Donnell of the California Strawberry Commission.
Much of the state's 855,000-ton annual strawberry yield comes from Watsonville, just south of San Jose, but the harvesting season there is still months away.
The current U.S. fresh strawberry supply depends on farmers in Ventura County, who produce far less.
Other sensitive crops include avocados, a $400 million industry generally harvested between March and October.
Temperatures throughout California fell on Thursday and Friday, ending up as much as 20F (11C) below normal. Snow and sub-freezing conditions forced a 17-hour closure of a key highway, Interstate 5, through the mountains north of Los Angeles.
Authorities reopened the highway Friday morning after thousands of motorists were stranded overnight on the winding stretch of road known as the Grapevine, or were forced to take circuitous alternate routes. (Reporting by Tom Brown and Dan Whitcomb; Writing by Dan Whitcomb; Editing by James B. Kelleher and Xavier Briand)