Sunday, April 25, 2010

No bees, no apples

They arrive quietly, in the middle of the night, unloaded from trucks, while they are sleeping. They come from as far away as Georgia and California, and they will be gone in a couple of weeks. The honeybees are descending on New England’s orchards.

That’s because, with the opening of the "king" blossom (the largest and center-most of the apple’s five-blossom clusters), pollination season has begun. While the temperate weather of the past week or so has slowed down the apple bloom, it is still running a couple of weeks ahead of most years due to the unseasonably warm weather the region experienced in early April.

Once the blossoms reach this stage, colonies rented from beekeepers must be moved in quickly—at night so the bees are "home" and not in flight. Sunny, mild days are needed during bloom to encourage strong bee activity. If we have extended stretches of rainy weather during bloom, it can seriously reduce the size of the year’s apple crop.

Pollination is necessary to the reproduction of all flowering plants. It involves the transfer of a plant’s male reproductive cells in pollen to the female reproductive structures of a flower, the stigma.

As the honeybee flies from flowers on one apple tree to those on another in the orchard, pollen sticks to its body. The pollen then rubs off onto the stigma each time the bee visits a flower. Pollen grains stick to the surface of the stigma, germinate and unite with the female cell in the ovary. After fertilization occurs, seeds develop and the fruit begins to grow. In this way, a honeybee may fertilize as many as 5,000 flowers a day.

Apples need more than one variety of pollen for the cross-pollination that ensures good fruit set. A Mac can’t pollinate a Mac, in other words. It needs a nearby Cortland, Empire or other variety to do the trick.

Not all of the orchard’s bees are imported. There are dozens of species of native wild bees that pollinate the apple blossoms. Many local beekeepers also supply New England’s apple orchards (and other farm crops), including hobbyists and, in at least one case, a high school beekeeping club.

It takes roughly a hive of bees to pollinate an acre of apple trees. The hives are often spread throughout the orchard, but the bees can travel far enough from a single location to cover an orchard with a two-mile radius.

Some orchards take no chances, putting additional pollen at the entrances of hives to guarantee that the bees coming and going will have a full payload

One grower in Connecticut recently told us that his supplier’s bee population is down 80 percent this year, a result of honeybee colony collapse disorder, an unexplained plague that has threatened the domestic bee population in recent years. But for the most part, New England growers—and their suppliers—seem unaffected

That may be because there are no great areas of monoculture of trees in New England, as there are in other regions. “There are many woodlots and other suitable non-agricultural areas in New England where there continues to be an active wild bee population,” says Mo Tougas of Tougas Family Farm in Northborough, Massachusetts. “There are plenty of bees to set our crop

“We bring in honeybees for insurance for our apple crop. Adding pollinators also may tend to give us better quality, as fruit will be more symmetrical with better pollination.”

No comments:

Post a Comment