More than 2 billion honeybees are moving off the state’s blueberry fields having done their annual duty in Maine.

The imported bees are the primary pollinators on the approximately 60,000 acres of blueberry plants and have been credited as a key factor in the increase in production in the past 15 years.

Although the weather during the rest of the summer will dictate how well the crop develops, conditions this year, especially during the pollination period, favored the bees and the blueberries, according to Tony Jadczak, the state apiarist.

“Things look good out there,” Jadczak said. “The weather was excellent during bloom. We had a couple of timely rains, but it was mostly hot and humid. And the bees like that.”

This year, Maine imported about 53,000 hives, down slightly from last year’s total of 57,000 as growers try to find the right balance of hives per acre. The bees are brought into the state mainly to pollinate the blueberry fields, although other growers use the migrant bees to pollinate such crops as apples, squash, cucumbers and even the relatively new crop of canola in Aroostook County. The bees come from as far away as Florida, Texas and California, and states in between, traveling south to north and back again pollinating a variety of crops.

Although agriculture officials in the sending states certify the bees as healthy, Jadczak said he inspects the hives that come into the state, checking for disease and for the presence of the African bee in the hives.

This year, 95 percent of the hives were excellent quality, he said, although hive owners still have to be on guard against diseases.

The fields themselves also were in good shape this year. Although it was a cold winter, there was a heavy snow cover that protected the low bush or wild blueberries, resulting in little plant damage.

“The plants are vigorous,” Jadczak said. “They were secreting a lot of nectar and the bees were actually making blueberry honey. We don’t usually expect that.”

Last year, the wild blueberry industry in Maine produced a record 100-million-pound crop. That crop was almost 35 million pounds higher than the 1999 crop, and was 15 million pounds higher than the previous record 84.6 million pounds.

The imported bees have played a key role in the crop increases over the years, according to Jadczak, who said there is a correlation between the increase in hives and in the wild blueberry production. In 1983, when he was hired by the state, Maine imported just 11,424 hives and the harvest was 44 million pounds. By 1990, the number of imported hives had more than tripled to 38,000 and the crop was up to 75 million pounds.

Although there are a variety of factors that affect the blueberry crop each year, the impact of the bees has been significant, Jadczak said. In 1999, the importation of bees peaked at 60,000 hives and the harvest was 65 million pounds, the five-year average for the industry.

Based on what he’s seen in the field this year, Jadczak said “things look real good again” throughout the state, although nobody is counting their berries before they’re raked, including Jadczak. But the conditions have been good.

The relatively dry spring has helped to inhibit the spread of disease in the blueberry plants, according to David Handley, a small fruit specialist at the University of Maine. The state is still a little dry, although there is water in the ground, but that’s not necessarily a bad thing at this point in the season, Handley said.

“A lot of moisture can be a problem,” he said. “Most of the disease we have comes from fungi, which do very well when there is moisture in the air.”

Rain can be a double-edged sword, Handley said. Too much in the spring can keep the bees in their hives resulting in low pollination. Too little rain during the summer months can affect the size of the berries, which depend on the summer rains. A drought can reduce the size of the berries, which means less weight for a $75 million a year crop which is sold by the pound.

The weather will determine what happens as the berries start to size up, and despite the favorable conditions, it’s still too early to predict what the harvest will be.

“Things are coming into line for a good season, but it’s still too early to tell,” Handley said.

Wild blueberry growers, processors, and university and government employees affiliated with the wild blueberry industry will meet next month for a regular meeting at the Blueberry Hill Farm in Jonesboro for the annual summer field day, at which they will make their predictions for this year’s harvest.

“It’s still a prediction, but at least they’ll have the green berries to look at,” Handley said.