The Top 5: What growers can do to improve pollination success

Inspect the bees you receive. A strong hive should have enough adult bees to cover eight to ten frames.

Honeybees are under unprecedented pressure, besieged by ­parasitic mites, viruses, diseases, and pesticide residues.

So, what can orchardists do to assure they will have pollination success during the bloom period, this year and years in the future?

Maryann Frazier, senior extension associate for Penn State University and part of its’ Center for Pollination Research, offers these five tips for a successful pollination season.

1 Get quality bees and place them at the right time.     

Have an ongoing relationship with your bee suppliers and realize they are having tough times, she said.
Inspect the bees you receive. A strong hive of bees should be at least two stories (two boxes deep), have a laying queen, four to six frames of brood, and enough adult bees to cover eight to ten frames.

While that’s ideal, much depends on how well bees come out of winter. With average losses of 30 percent, and many beekeepers losing 50 percent or more of their colonies each year now—an unsustainable level—­understand that compromises may have to be made.

The best time for placing bees is to move them in at 10 to 25 percent bloom, or earlier if king bloom set is most important. Eliminate competing flowers on the orchard floor, like dandelions.

Place colonies in groups of four to eight (or even larger groups in large orchards) in sunny, wind-protected spots. Entrances that face east or southeast encourage bee flight.

2 Have a pollination contract.     

A pollination contract is very useful to both grower and beekeeper. Frazier provides a model contract for Pennsylvania growers in the Pennsylvania Spray Guide (available as a PDF on the MAAREC Website: https://agdev .anr.udel.edu/maarec/wpcontent/uploads/2010/03/Pollination_Contract.pdf).

The contract outlines responsibilities of the beekeeper and of the grower. The beekeeper agrees to provide a number of hives of certain strength, for a certain specified period, to open a few hives for the grower’s inspection, and to place them properly.

The grower agrees to provide accessible sites for the colonies, not to apply pesticides while the bees are being used as pollinators, and the contract has space for listing which pesticides and methods of application the grower may use.

The grower agrees to dispose of pesticide solutions in such a way that bees won’t contact the material when searching for water, and to provide watering facilities for the bees if none are available within a half-mile of the hives.

Should the grower need to spray hazardous materials, he/she should give the beekeeper 48 hours notice and pay for the cost of moving the bees away. The contract should also state the rental price.

3 Communicate with your bee supplier.        

Communicate with your bee suppliers, not only to advise them of your bee needs for the upcoming season but to hear their assessment of the survival and strength of their colonies.

The first real test of how the nation’s colonies fared over the winter comes with the almond pollination season, when more than 1.5 million colonies of bees trek to California. “The best measure of the number of colonies available for pollination nationwide is what they look like going into and coming out of the almond crop,” Frazier said.

In mid-February, there was indication that the number of hives available for almonds was down by some 100,000 to 200,000 colonies. “That’s a bad sign,” she said.

4 Protect your pollinators.    

Much work by several collaborating members of Penn State’s Center for Pollinator Research has focused on pesticides. Both honeybees and native bees are being exposed to and need protection from pesticides.

“Growers should not apply insecticides or fungicides during bloom,” she said. “It’s known that growers don’t think fungicides are a problem, because they have low toxicity, but we and others have found that they can synergize and increase the toxicity of certain insecticides by as much as a thousandfold.”

If pesticides were the single major problem, the links would have been made by now, Frazier said. “Thinking now is, it’s not just one thing acting independently to cause colony collapse disorder or the overall decline of pollinators—not pesticides, not mites, not diseases and viruses, not nutrition. It’s likely a number of these things interacting. For instance, mites, pesticides, or poor nutrition can suppress the immune function of bees so they can’t fight off the challenges of viruses or other disease.”

5 Provide a refuge.    

Growers can be misled into thinking that their orchards, with those billions of blossoms, are like candy stores chock-full of pollen and nectar.

“Both honeybees and most native bees need a diverse source of pollen,” Frazier said. “Our studies have shown that even during apple bloom, bees collect pollen from other plants.”

Bees in almond orchards have exactly one food source—almond flowers growing in an otherwise plant-free desert.

Pollinators need places of refuge that are both free of pesticides and provide a source of pollen. The dilution effect of a source of pesticide-free pollen can reduce the impact of pesticides bees might pick up in the orchard or elsewhere, Frazier said.

Studies are under way to identify the best mixture of plants, and there is some technical advice and government money available to orchardists who plant them.