By Jim McCausland, Sunset Magazine
One of the first things any kid learns about honey bees is that they're great at cross-pollinating flowers, carrying pollen from flower to flower on their legs. Well-read gardeners learn that bees also help flowers self-pollinate: their buzzing shakes pollen free so that some kinds of plants, like tomatoes, can self-fertilize. Recent research shows that buzzing can also help drive away caterpillars.
Here's how it works. Honey bees are vegetarians, so they pose no real threat to leaf-eating caterpillars. But wasps are carnivores that seek and eat caterpillars. In defense, many kinds of caterpillars have fine hairs that pick up the buzz of wasps that happen to be cruising through the vegetable patch. When caterpillars detect that buzz, they drop to the ground to get out of harm's way.
Fortunately for gardeners, caterpillars can't tell the difference between the buzz of honey bees and the buzz of wasps. When they hear either, they usually play it safe and drop off the plant they're munching until the perceived threat passes.
To test this theory, scientists caged two vegetable patches. One contained only caterpillars, while the other held caterpillars and honey bees. By the end of the test, the patch that contained bees had less damage to plants than the one without.
The take-away message: interplant flowers with your vegetables. When bees come to feed, caterpillars will be too busy fleeing to eat much.
