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Storms threaten to disrupt pollination

Issue Date: February 22, 2017
By Christine Souza
Recent rains flooded an orchard at Bullseye Farms in Woodland, above, threatening bees brought in for pollinating the farm’s almond crop. Bullseye’s beekeeper later remedied the situation by adding more pallets to raise bees out of standing water. Wet, muddy conditions were a challenge as beekeepers tried to move bees into almond orchards, resulting in many stuck forklifts.
Photo/Nick Edsall, Bullseye Farms
Awaiting a downpour in an almond orchard near LaGrange, above, beekeeper Ryan Cosyns of Madera-based Cosyns Bee Co. added more pallets to raise beehives above any water that might collect in the orchard during storms.
Photo/Ryan Cosyns, Cosyns Bee Co.

It wasn't long ago that commercial beekeepers had to purchase totes of water so honeybees had enough water to survive the California drought. Now, beekeepers are placing colonies on stacked pallets so hives sit above water in flooded almond orchards.

Just as the almond bloom begins across California, a series of storms threatens to complicate pollination for the state's almond crop.

Each year during bloom, which usually occurs from mid-February through mid-March, an estimated 1.8 million beehives are placed in orchards for pollination of the state's 900,000 bearing acres of almonds.

David Doll, University of California Cooperative Extension farm advisor in Merced County, said trees are "well into pink bud," where blossoms begin to open within the trees. Orchards that were seeing 2 percent to 5 percent bloom could develop to 20 percent to 30 percent, due to several days of warm weather last week, he said.

"If it is a real heavy rain, it can actually disrupt the pollination process," Doll said. "Heavy rain can knock the blossoms off—especially if we have hail—and can damage flowers, making them non-receptive to pollination."

In the days leading up to the storms, almond growers rushed to apply fungicides to prevent fungal diseases in almond trees. Many farmers scheduled aerial applications in areas where they were unable to get other equipment into the orchards due to wet conditions.

"Bloom is really starting to come along and now we're slammed," Eric Genzoli, who grows almonds with his family in Turlock and Hughson, said in the days before the storms hit. "The weather is getting bad and we are probably going to miss the window (for applying fungicides), but we'll see. We're doing all that we can."

Doll explained that fungicide applications applied prior to a storm will last about a week to 10 days, which means farmers would have to consider a second application as soon as they can gain access to their orchards. Doll said there are a number of fungal diseases that "can blight fruit and cause crop losses."

A set of bee "best management practices" released by the Almond Board of California in 2014 recommends fungicides be applied in the late afternoon or evening, when bees and pollen are not present.

Storms could also reduce the number of effective pollination hours by reducing the amount of time honeybees are flying, which can ultimately reduce fruit set. Honeybees generally don't fly in the rain and they typically forage at temperatures above 55 degrees.

"Cooler temperatures associated with the rain often increase the length of bloom but generally, negatively impacts crop set because you are having disruption of the flower and the pollination process," Doll said. "With the trees opening up coming into this rainstorm, the expectations are going to be a bit lower this year. I think it is going to be a challenging year."

Billy Synk, director of pollination programs at Project Apis m.—a group established by farmers and beekeepers to fund honeybee research—said the textbook answer about the length of almond bloom is that it lasts for five to six weeks.

"Hopefully, we have a little bit longer bloom period and that can help mitigate the effects of the reduced flight hours," Synk said. "By the time it warms up in the morning and the fog dries off and maybe the storm happens at 2 in the afternoon, that day might only have two flight hours. You need strong hives stocked at a good rate (two hives per acre) to make the most use out of those two hours."

Mel Machado, Blue Diamond Growers director of member relations, noted that honeybees were still being brought into some orchards, but for the most part, he said, bloom is getting started across the state.

"There are individual orchards that are way ahead of others of the same variety, but we don't know yet; it's just getting started. We'll be peaking in a lot of areas (regarding bloom) by the end of the week," Machado said. "Weather forecasts are indicating that we'll have some issues, so we'll just have to work our way through them. It can rain at night and be good during the day, so we've seen that too."

While almond growers have plenty to be concerned about, beekeepers who need to move in and out of almond orchards either to place beehives or check on honeybees were dealing with saturated soils and challenging conditions.

"It seems like it's the wettest year we've ever had moving the bees out of the bee yards to go into the orchards," said beekeeper Bob Seifert, owner of Bear River Honey Co. in Sheridan. "We just dollied the hives out to the road because our forklift couldn't get in there, and that's a first."

Some beekeepers are having to place colonies on top of stacked pallets to keep them up off of flooded orchard floors. Seifert said he is placing some bees along gravel roads adjacent to the orchards.

Even with challenging weather and access issues, Seifert said he remains confident about almond pollination this season.

"We feel that our bees are strong enough that between the storms and during breaks in the storms, they will get out and do a really good job," he said. "This year, because it is so warm, I think bees are going to get out and get a good pollination, no matter what."

(Christine Souza is an assistant editor of Ag Alert. She may be contacted at

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

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