Damage from long cold spell appears slight
By Ching Lee
Most of the state's crops appear to have weathered the freezing temperatures this month without significant damage, but vegetables from Southern California may be in shorter supply as farms try to catch up on harvest.
Imperial County farmer J.P. LaBrucherie, who's currently harvesting head lettuce, romaine and broccoli in El Centro, said the cold temperatures have "significantly slowed" the growth of his plants. With ice covering his crops through most of each morning, he said his crews were picking much later in the day to allow the plants to thaw.
"That reduces the amount of time you have, especially now in the winter. So it's harder to get all the products harvested," said LaBrucherie, who serves as president of the Imperial Valley Vegetable Growers Association.
The delays have resulted in a limited supply of vegetables from the region, leading to higher market prices for growers, he noted.
Aside from having to remove some outer leaves of the lettuce plants, LaBrucherie said he has not seen any major damage such as discoloration or blistering to his crops. He noted that before the cold snap, Imperial Valley weather was actually too warm and his crops were coming in too early. In that respect, the extreme heat affected the quality of his crops more negatively than the cold, he added.
Crops such as citrus, avocados and ornamentals in San Diego County also appear to have made it through the freeze relatively unscathed, said Eric Larson, executive director of the San Diego County Farm Bureau.
Some citrus growers reported minor damage to new growth on their trees, he noted. Most nursery growers he spoke to said their plants suffered some type of tip burn, but it appears those plants will grow out of it.
What's still unclear is the extent of the damage on avocado trees, he said. Some farmers have reported seeing brown stem, which is freeze damage to the stems above the avocados. If that part of the stem freezes, Larson said, the fruit attached to it will eventually drop.
"So it's kind of wait and see what happens," he said. "In some of the lower-lying areas, that's where the issue lies."
Ben Faber, a University of California Cooperative Extension farm advisor in Ventura and Santa Barbara counties, said he talked to one grower last week who reported seeing brown stem in the lower quarter of his orchard.
"I said, 'Kiss those goodbye,'" he said. But he said he also advised the farmer to look higher in his orchard to determine if there are stems that are only partially brown, as fruit on those stems may continue to grow.
Faber said he has not heard of any significant harm to crops in San Luis Obispo or Santa Barbara counties, as farms along the coast did not experience the same cold temperatures as the inland areas. In Ventura County, growers did report leaf damage but no major fruit damage to their avocado and lemon trees, and any losses were not widespread.
Strawberry growers in Ventura, Orange and northern San Diego counties also reported some damage to their crops, but those who used frost protection suffered very minimal damage, said Carolyn O'Donnell, spokeswoman for the California Strawberry Commission.
She noted some farmers in Ventura County deployed helicopters to fly over their fields as one frost protection method, while others grow strawberries under hoop houses, which automatically protect the fruit from extreme cold.
"The great news about strawberries is that they continuously bloom and produce fruit, so you always have production in various stages. It's not like a peach crop where you have one set of blossoms and that's your harvest," O'Donnell said.
In another week, growers will have a better sense of whether there's additional damage that shows up, but at this point, she said there are no indications of any serious supply issues due to the minor damage to the state's strawberry crop.
The frost protection measures that farmers have had to implement, including using wind machines and turning on overhead sprinklers and irrigation, are very expensive, said Ryan Jacobsen, executive director of the Fresno County Farm Bureau. Fortunately, it looks like they worked, he noted, although adding that the county agricultural commissioner's office is still cutting open citrus fruit to assess the damage, which looks to be "fairly minimal" so far but can show up days to a week later.
Alyssa Houtby of California Citrus Mutual said damage to the state's citrus crop appears to be minimal—with perhaps more damage to mandarins and lemons while navel oranges fared better.
Other permanent crops such as grapes, nuts and other tree fruit are dormant and are expected to do OK, as there was enough moisture in the ground from plentiful rains received earlier this month, Jacobsen said.
"Those types of permanent crops actually require a certain number of chill hours under 45 degrees during their dormancy period," he said.
Cindy Fake, UCCE farm advisor for Placer County, which is well-known for its mandarins, said most of that fruit has been harvested except for a few clementines, and what's left on the trees suffered very minor damage.
She noted that Meyer lemons, another signature crop in the region, did see more damage because they are less cold-tolerant than mandarins. Meyer lemons have thinner skin and the damage tends to occur as oil cells in the skin burst, seeping the oil into the fruit and making it bitter, she said. But reports she's gotten indicate there hasn't been that much of a problem except in a few scattered trees.
Fake also noted that most of the county's citrus trees are grown on slopes at 400 feet or higher elevation, so the region doesn't get as cold as some parts of the valley.
Franz Niederholzer, UCCE farm advisor for Yuba, Sutter and Colusa counties, said aside from citrus, the only other crop of concern in his region is olive trees, which can be susceptible to olive knot, a bacterial infection that occurs at low temperatures. But he said most growers are aware of the potential for the disease and were treating their trees.
(Ching Lee is an assistant editor of Ag Alert. She may be contacted at email@example.com.)
Permission for use is granted, however, credit must be made to the California Farm Bureau Federation when reprinting this item.