Frost damage emerges across Northern California

Updated April 25

With temperatures continuing to hover near freezing, Lake County growers are still concerned about crop damage and they're hesitant to say the worst is over. Early morning temperatures in Lake County today remained at freezing levels, reported Lake County Farm Bureau Manager Chuck March.

Blackened leaves on trees in this Tehama County walnut orchard resulted from a spring freeze that hit crops in much of California.

Several crops, including grapes, pears and walnuts, have all been damaged by the severe cold snap, and March said, "The frost season is running into May and our farmers worry there's still more cold weather ahead. These unseasonably cold temperatures have gone on for weeks. The conditions may have damaged some crops, but not others. It's hard to tell right now."

He said farmers and agricultural officials will be out surveying next week to get a better idea of how bad the county's agricultural sector was hit.

"Depending on the variety of walnut, we're hearing about extremely high losses," March said. "The later varieties, however, haven't been hurt as much. It's a timing issue.

"Pears are showing a lot of black centers, meaning the cores were frozen," March said. "That fruit won't set. Pear growers may be facing a disastrous crop loss."

Accounting for $43 million in production, winegrapes are Lake County's top commodity, followed by Bartlett pears at $11 million. English walnuts account for another $3 million.

"We're hearing about damage in our winegrape vineyards throughout the county," he said. "Depending on warming conditions, we should have a pretty good idea in the coming weeks how much production has been lost in the vineyards."

Farmers throughout Northern California are saying April temperatures and the hard freeze last week are the coldest they've seen in decades. In dark hours of Sunday and Monday morning last week, temperatures plunged into the 20s throughout many Northern California growing areas. Crop protection measures didn't always save orchards and vineyards from the worst effect of the cold.

The U.S. Department of Agriculture's Risk Management office in Davis has been receiving damage reports for the following crops: prunes, winegrapes, table grapes, apples, pears, walnuts and stonefruit, including peaches, plums and nectarines.

"The most important information to convey to growers is that they should report their notices of damage to their insurance agents as soon as possible," said Zandra Pendarvis, USDA's California Risk Management deputy director.

"Crop conditions are still being monitored because the full extent of damage just is not known at this time," Pendarvis said. "We're taking a wait-and-see approach, but in the meantime, growers are responsible for giving notice that a damage event has occurred."

Crop insurance agents say their phones are ringing off the hook. In the past several days, agents and adjusters for NAU Country Insurance Company, the largest writer of multi-peril crop insurance in Northern California, has received more than 600 reports of crop damage in the past few days due to the freeze.

For comparison, NAU Country Insurance Company Manager Larry Heitman said statewide they had only received about 200 calls since January. Commodities hardest hit based on claims appear to be walnuts, prunes, peaches and winegrapes, but damage also is being reported for pears, apples and some young tomatoes.

"Pears aren't a huge crop, but it appears they have been terribly hurt," Heitman said.

In Mendocino County, winegrape grower Tyler Nelson said he just participated in a meeting that included growers from Mendocino and Lake counties and said, "I didn't talk to a single person who didn't have some damage.

"I was hoping to do some consulting work on a vineyard in Lake County, but the owner called and said don't bother coming down. He said temperatures dropped down to 24 degrees for six hours and he said the whole vineyard was a loss."

Nelson said in his own Mendocino vineyards damage varied by block.

"In one 10-acre chardonnay block we had about a 30 percent loss. In a neighboring vineyard we had about a 10 percent loss. In some cases the frost protection equipment just couldn't keep up. It was simply too cold."

Warming temperatures will stimulate crop growth and help farmers and agricultural officials develop more accurate damage estimates. They will be able to see which plants appear to be reviving and which have been too damaged to survive or produce for the coming season.

Farmers throughout California are reporting widespread and considerable frost damage, although crop losses in Northern California appear to be most significant. As farmers assess the impact of last weekend's cold snap, they're becoming dismayed as the signs of damage mount.

In response to the cold, farmers did crank on irrigation systems, run wind machines around the clock and respond to alarms triggered by low temperatures. In some areas these tactics may not have been enough to protect crops in the earliest stages of development.

"Usually this time of year we're more concerned about frost damage to our almond crop," said Tod Kimmelshue, whose family farms in Butte County and who is a California Farm Bureau Federation director. "But the almonds didn't get much damage during this cold weather event.

"What did get damaged in the northern Sacramento Valley is the walnut crop. Historically farmers don't do much frost protection for walnuts. This freeze came out of nowhere and hit at the worst possible time for walnut growers.

"Now, there's a real possibility that the young walnut trees will have wood damage. Even with serious damage, the trees probably won't die, but it will set production back at least a year."

"We had pretty severe crop damage in our peaches," said Sarb Johl, who farms in both Yuba and Sutter counties. "With walnuts it's still a little early to tell, but we have a lot of pit burn. With peaches, we've got some orchards that are a complete wipeout. Other orchard acres are damaged, but the severity is unknown at this stage—it could be 50 percent to 75 percent."

With peaches, he said, "If the pit freezes, it's like shutting off the heart of the fruit. After that nothing works. We're already seeing the young fruit turning black and shriveling up."

County agricultural commissioners are collecting information that could lead to disaster declarations, but it will take more time to determine the extent of economic loss. In some cases, it's clear that individual farmers may see crop losses approach 80 percent to 100 percent, depending on location and crop.

Following is a roundup of initial damage reports by region:

Sacramento Valley
Sutter County Agricultural Commissioner Mark Quisenberry said reports are coming in that walnuts, particularly in Butte County, were hit hard. "Temperatures in Butte dropped to 24 degrees. We got down to 29 in some pockets."

"The Prune Bargaining Association said that growers in the Chico area suffered serious losses, in some cases 100 percent. In Sutter County, our preliminary prune losses range from 25 percent to 100 percent, depending upon the pocket where the crops are being produced when the low temperatures hit.

"We also have damage to late-variety walnuts, peaches and to a more limited extent, canning tomatoes."

He also noted that diversified growers who serve farmers' markets with crops like beans, squash and cucumbers have been hard-hit, as well.

Another segment hit by the cold snap may be tree nurseries that usually graft vulnerable budding stock for commercial orchards at this time of year, Quisenberry said.

Newly planted orchards also are vulnerable to severe cold and last weekend's temperatures may have caused damage to tree wood, as well as external tissue.

Johl said that while there's crop insurance available for peaches, the margins for producing the crop often don't pencil out when additional premiums are factored in.

Beyond catastrophic coverage, he said, "it's hard to justify the cost of the premium compared to the risk. This cold spell is very unusual and you don't often see this level of damage at this time of year."

In orchards with new plantings, he said there are trees that completely burned and the leaves have already fallen off the young trees.

North Coast
Winegrape growers throughout Lake, Napa, Sonoma and Mendocino counties are calling last weekend's low temperatures the worst spring frost in decades and say they expect millions of dollars in losses to the winegrape crop when the full extent of damage is known.

"We experienced pretty widespread frost in the state's grape growing areas, both Sunday and Monday morning," said Nat DiBuduo, president of Allied Grape Growers.

"We've heard from our growers in Lake, Napa and Sonoma. Depending on the location of the vineyard, in some cases, damage is from 5 to 10 percent, in other cases we're getting reports from growers of 50 to 80 percent, depending on grape variety and vineyard location

"So, damage is widespread and Kern County growers have been affected as well. And, even though growers have had wind machines running for days and they applied water, in some cases it didn't prevent damage."

Grapevines can rebound with secondary buds, DiBuduo said, but these typically aren't as fruitful as primary buds.

San Joaquin Valley
In Tulare County, many areas were glazed with frost, but Tulare County Deputy Agriculture Commissioner Marilyn Kinoshita said it's still too early to know the extent of damage and loss. In some eastern pockets, temperatures lingered in the 27 to 28 degree range for many hours, which can damage citrus, one of the county's major corp.

So far, Kinoshita said formal damage assessments haven't been filed by growers or citrus groups with the commissioner's office.

When all damage to all crops in Tulare County is tallied, she doesn't anticipate that countywide it will reach the 30 percent threshold needed for a disaster declaration. She cautioned, however, that damage assessments are still highly preliminary.

"We noticed some varietal and maturity differences in damage that appeared in Tulare County vineyards. Location appears to be an important determining factor in the extent of damage. With Thompson seedless grapes, one of the earliest varieties to be harvested, our inspectors saw a wide range of damage, some of it severe.

"We also looked at a pomegranate orchard and the damage there may result in a complete lost crop for 2008 for that grower," she said.

In addition, Allied Grape Growers said it received reports of vineyard damage in Clements and into the Turlock area.

There also has been some damage reported to plums in the Exeter and Porterville areas. The extent of damage is not yet known. However, orchards in that area usually have a heavier set than plum orchards at lower elevations.

Cherry growers say they will continue to inspect their trees for signs of damage, but that they believe the crop did not suffer harm from the cold snap.

Central Coast
Frost damage is being reported to vineyards in the Paso Robles area, although the extent is preliminary. Growers in that area are reporting nighttime temperatures during the weekend as low as 27.

Strawberry farmers say temperatures stayed above freezing and their crops escaped damage, though chilly temperatures slowed growth of the berries somewhat.

(Kate Campbell is a reporter for Ag Alert. She may be contacted at kcampbell@cfbf.com.)

Permission for use is granted, however, credit must be made to the California Farm Bureau Federation when reprinting this item.