Crop impact uncertain: Hard freeze hits early almond bloom

A bone-chilling mid-February freeze at the beginning of bloom shook 6,000 California almond growers, pest control advisers (PCA) and almond handlers like an almond tree in the grasp of a powerful tree shaker.

No area of the state was spared. Below freezing temperatures were recorded in orchards from Red Bluff to Bakersfield. Temperatures dipped to 20 degrees in northern California. Growers there frost-protected for seven straight nights. It did not get that cold in the central and southern San Joaquin Valley. However, it was below 30 for several hours each night for several days as well.

No question some blossoms were frosted out, particularly on early blooming varieties. NePlus, Peerless and Sonora were most often mentioned by PCAs, growers and University of California Cooperative Extension farm advisors as hardest hit.

However, the same people are saying it is too early to tell if there was a major crop loss from the statewide frost. Damage was definitely spotty, depending on orchard location. Trees in swales were hit hardest. It will be next month or perhaps May before everyone gets a good handle on freeze damage and the crop size. The subjective almond crop estimate scheduled for May 10 release will be telling about frost damage.

Prices jump

Although no one is yet hazarding a crop loss guess, immediately after the cold snap the industry shivered and spot prices for almonds jumped 60 cents per pound overnight on rumors of widespread damage. Before the frost, prices of about $1.60 per pound to growers were being quoted. After a week of cold temperatures, it cracked past $2 pound.

California's almond marketers desperately need another one-billion-pound crop from the state's 550,000 acres of bearing almond orchards like the crops produced for three years from 2002 to 2004. The almonds are needed to meet unprecedented world demand and to moderate prices that skyrocketed in the wake of a weather-reduced '05 crop of about 900 million pounds. Markets were lost due to high prices over the past year, and the industry is fearful a second short crop could cause long term damage to a market they have spent millions building demand in preparation for the 1.5-billion-pound crops that are not too far in the future.

Garret Nydam, PCA with Mid Valley Agricultural Services in Hughson, Calif., said the frost severely damaged NePlus and Sonora orchards. The crop is “gone” from those varieties. Young orchards were hit hardest. “It was lowest (bloom time) temperatures I have seen in 15 years.”

Aaron Hackler, PCA with Hughson Chemical in Hughson, Calif., said one of his growers turned on micro sprinklers to frost protect during the cold snap and found spaghetti micro irrigation lines filled with ice at 10:30 p.m.

Use all protection

“The grower kept running the system and it cleared out,” said Hackler. Growers who could flood irrigate did. Others ran blowers in orchards to circulate air and prevent frost from settling on tender flowers.

“There has been damage,” said veteran Riverbank, Calif., PCA Norm Kline who is also a grower. “However, I cannot say how much. Orchards that have been taken care of fared better in the frost than weak orchards.”

A silver lining in the cold snap is the bread and butter California almond variety, Nonpareil, was just beginning to bloom when the frost hit and likely suffered minimal damage, if any at all. About 200,000 of the state 550,000 acres are in Nonpareil. The frost time bloom estimate for Nonpareil ranged from 10 to perhaps 40 percent, depending on the region. Nonpareil had a lot of blooming left to do after the frost. This may be the industry's saving grace.

PCAs say the '06 almond bloom was very strong coming off a low production year last season.

“I think the trees rested last year with the smaller crop and came back with a huge bloom this season,” said Madera, Calif., PCA Mark Carter, consultant on orchards throughout the central valley.

Depending on who does the estimating, it takes only from 20 to 30 percent of the flowers to develop into harvestable nuts to make an excellent crop.

“Even in the best of years, you do not set more than 25 to 30 percent of the flowers,” said Stanislaus County farm advisor Roger Duncan.

Strongest flowers

Duncan described the frost damage in his county as “spotty and only on earliest blooming varieties. My thought right now is that the February frost will not have a huge effect on the total crop.”

Although the frost was early in the year with no more than half the Nonpareil flowering, it is the earliest flowers that are the strongest and set most of the crop, noted Duncan. “Hopefully, flowers that opened later set a larger percentage of the crop.

“We'll have a better idea in May where we stand,” he added.

He noted growers are more concerned about frost after bloom as the trees move toward the nutlet stage. It does not have to get much colder than 32 to damage young, tender nutlets.

Mark Freeman, Fresno County, Calif., nut farm advisor, said he had not heard reports of Nonpareil damage in the county. However, there was damage to NePlus and Sonora.

Freeman echoed Duncan's observation that trees are more susceptible to frost damage in the nutlet stage. “It takes 23 to 26 degrees to damage pink blooms and 26 to 28 degrees at full bloom. However, it takes only 29 to 30 degrees to cause damage at the nutlet stage.”

Madera County, Calif., farm advisor Brent Holtz said “orchards that were supposed to have a lot of damage seemed to be OK” a week or so after the frost incident.

Some of the Sonora trees he looked at “were not bad” because after the frost the trees continued to bloom.

“It is a numbers game. You may lose 20 to 30 percent of the blossoms, but that does not mean you have lost 20 to 30 percent of the crop,” Holtz noted.

Kern County Farm Advisor Mario Viveros noted there were long frost periods at night over several days, which can cause serious damage.

“Damage varied from location to location. Nonpareil ranged from 12 percent frost damage of early blooms to maybe 80 percent loss. Sonora was more susceptible, but it proved a pretty hardy variety in the frost.”

Viveros was the only farm advisor who said the bloom quality “was not there.”

Bloom earlier

Butte County is above the winter Tule fog area and almond trees blooms earlier than Southern San Joaquin Valley orchards. UCCE farm advisor there Joe Connell said Nonpareil fared “pretty good” in the frost. Butte County was the coldest almond growing areas during the frost period.

“It got down to 20 to 21 degrees on the outside of some orchards and frost protecting in the orchard will bring that up to only 25 to 26 degrees. Yes, it was pretty chilly.”

“We have lost some crop; how much is hard to say. We only need to set 25 percent of the flowers to make a good crop. So, if we lose 3 out of 4 flowers, we still should be OK. There was a beautiful bloom before the cold came,” said Connell.

Connell noted when the bloom is heavy like this year, there is competition between flowers for carbohydrates and sugar and that has an effect on crop set. “If we have taken some of those flowers out by the frost, there may not be as much competition among the remaining flowers and we could have a higher percentage set” than would be the case had the frost not taken out some of the flowers, he noted.

Bee pollination

Remember all the prophets of doom who said the big crisis facing California almond growers this year would be a shortage of pollinating honeybees?

Those prophets were last seen tossing their crystal balls into irrigation canals because the bee supply was plentiful — but expensive — during bloom this year. Bees cost as much as $140 per hive or more to rent for pollination this year, but bee strength was reported strong. Growers use from two to three hives per acre to pollinate.

“Isn't capitalism great?” laughed Connell, who acknowledged that when the prices became high enough beekeepers and their bees came swarming into California from all over the U.S.

One PCA said a beekeeper told him it cost only about $15 per hive to truck in bees from out of state for almond pollination. Rental prices above $100 per hive offer a sweet profit.

“Bees came into the state strong this year for a change,” said Kline.

Bees were so plentiful there were classified ads in newspapers from beekeepers looking to place hives. Several farm advisors like Connell said they received calls from beekeepers looking for growers who needed to rent hives.

Cold affects bees

The dreaded varoa mite beekeepers kept blaming for weak hives last year seems to have disappeared with the stratospheric bee rental rates.

Many PCAs and growers were more concerned about the impact of the cold and often rainy weather on bee pollination than they were about frost.

Bees do not like to forage when it is windy, below 55 degrees and overcast or raining. Fortunately, there were nice stretches of warm days between cold spells and storm fronts, noted Freeman.

However, several commented the bees were aggressive this year in less than ideal conditions.

“We were out checking orchards one morning after the frost and the thermostat in the pickup was in the low 40s but you could hear the bees buzzing,” said Stanislaus County farm advisor Duncan.

Hackler said some beekeepers were even recommending to growers that they call county ag commissioners to verify hive strength. Colony strength was definitely better this season.

A more compelling concern was the lack of winter chilling hours and its impact on bloom. Many were expecting a staggered or prolonged bloom.

That was evident in Stanislaus County Carmel/Nonpareil orchards.

Hackler said Carmel did not bloom on time. “Carmels were so far behind in bloom. When the Nonpareils first popped there was nothing there to cross pollinate with. Guys with three varieties in an orchard, however, had overlapping blooms. Guys with 50-50 Carmel/Nonpareil were a little worried,” he noted.

Duncan said Stanislaus is a “big Carmel area. The lack of a bloom overlap may reduce yield potential,” he agreed.

California almonds are the one California crop most susceptible to the vagrancies of the weather. The entire crop begins blooming in early to mid February when the state is still very vulnerable to winter storms. This year's frost has gone to the top of the coffee shop chat list. It is usually rain playing a cat and mouse game with growers and PCAs.

Growers must apply fungicides ahead of rain to prevent a wide array of diseases, and it often involves a 7- to 10-day spray schedule to keep ahead of Pacific storms.

There was considerable rain last year just like growers have seen this season. However, last year temperatures were warm, not cold like 06. Warm and wet are an ideal combination for disease development.

Less disease

“In a cold year like this disease pressure is not too high; not as high as last year,” aid Hackler.

“We are in the best position we have ever been in terms of fungicide choices. We have a lot of good choices.” said Nydam. Ten years ago PCAs had basically Benlate, Captan and Ziram from which to choose.

“We have a lot more today and if the spray dries within six to 12 hours after application, you can count on a good 10 days of control because most of them are translaminar,” Nydam explained.

Although the fungicide arsenal is stocked, Hackler says he wants to keep them all around for a long time and that is why he rotates chemistry to mix modes of action.

“We do not want to see resistance. That's why I rotate,” said Hackler.

One of the newer fungicides on the market is Scala from Bayer CropScience. “I have used a lot of Scala this year, particularly in fields where I used other products last year.” The new fungicide is primarily for early season diseases like shothole, brown rot and botrytis and Hackler said it is “very economical.”

These are primarily bloom-time diseases. “We are seeing more foliar diseases like Alternaria Leaf Spot later in the season.”

PCAs also have reported seeing more powdery mildew on trees late in the season on tissue as well as the nuts.

“I think a lot of that is due to the moist microclimates we are creating in the more densely planted orchards where there is not much air movement,” he said.

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