Pesticides: To bee or not to bee
December 31, 2012
After my article on pesticide safety, a reader asked me to mention that pesticide use can kill honeybees, which are important in the food chain. Yes, honeybees are important, and yes, pesticides can kill bees, all bees and other beneficial insects, not just honeybees.
Drift of toxic sprays, dusts that adhere to the bees themselves, contaminated water on foliage or flowers or contaminated pollen and nectar can all harm bees. To protect pollinators, do not use insecticides during the period of bloom. If insecticides are the only option, apply them only in the late evening when bees are not present. Use products that are least toxic to bees. Don’t spray near bee nests.
People may not realize that bees other than honeybees play an important pollination role. Nevada’s state entomologist, Jeff Knight pointed out in a recent lecture that honeybees, which are domesticated rather than native insects, are only one species of bee out of the 3,000 to 4,000 species of bees in Nevada and that honeybees are not the best pollinators.
Knight suggested people look to other pollinators such as the many types of native leaf-cutter bees including blue orchard and mason bees. Because these bees stay in the flower longer than honeybees do, they are actually more efficient pollinators than honeybees are. Bumblebees are better pollinators than honeybees too.
The blue orchard bee is a native pollinator in Nevada built to order for home gardeners with fruit trees. This small, shiny black bee is a better pollinator than the honeybee. It is easier and safer to handle because it does not swarm, seldom if ever stings and does not pose a risk to a gardener or a neighbor.
This busy bee may visit an average of 1,600 flowers per day, pollinating over 90 percent of the blooms. A honeybee visits 700 flowers and pollinates less than 50 percent. The BOB begins pollinating in the morning at 55 degrees, while the honeybee starts when the temperature is warmer.
Since the BOBs build nests of mud in abandoned beetle holes in the ground, trees and wood, gardeners can entice them to their yard by creating nesting sites for them: drilling 5⁄16-inch holes at least 3 inches deep in blocks of wood or setting out bundles of unwrapped, paper soda straws. For more information on attracting the blue orchard bee contact me at 887-2252 or email@example.com and ask for the Blue Orchard Bee fact sheet, FS-02-11.
JoAnne Skelly is the Carson City/Storey County Extension educator for University of Nevada Cooperative Extension.