Treat insects with caution

Bees and hornets can start to become a nuisance around homes at this time of year. However, remember that many of these insects are beneficial pollinators and care should be used before destroying them. "Especially in the spring and early summer, honey bees may swarm in large groups and can look threatening to homeowners," said John Church, University of Illinois Extension Educator, Natural Resources, Rockford. "But, in reality, these beneficial bees are just searching for a new home."

U. of I. entomologists offer the following tips on bees and wasps.

Honeybees are amber or brown and black banded, hairy and about half-inch long. They nest in hollow tree trunks and build colonies that may contain tens of thousands of individuals. When nests get congested, some of the bees will leave in swarms of several hundred looking for new nesting sites, usually in the spring. The bees often form a mass on a tree branch or other support for a few days until a permanent site is found. Control is usually not recommended or necessary, since most of these swarms leave on their own within a few days. It is recommended to leave the swarm alone in the meantime. Honeybees in swarms are usually docile and those with colonies in trees rarely attack, unless provoked. Swarms that remain after a week may need to be removed by a beekeeper or professional pest control operator. Treating with an insecticide should be used only as a last resort. Also, swarms that start to invade structures may need to be controlled or removed, since the honey and wax can become a serious problem within walls or other areas of a building.

Other types of bees and hornets also become more prevalent throughout the summer. Bald-faced hornets are the insects that build football-sized and shaped "paper nests" in trees and shrubs. Again, unless the nest is in a "high-traffic" area for humans, it is best to just leave it alone. Yellowjackets present the major nuisance for most people as their populations builds during the summer and fall. They are half-inch-long, black-and-yellow-banded wasps that many people call "bees." They build up in population throughout the summer and are attracted to food and drinks, which brings them into more contact with people. They live in underground nests, woodpiles, pile of brush, hollow tree or a hole in the wall of a house. Late in the summer, nests may contain several thousand wasps. Of the Illinois bees and wasps, this is probably the most likely to sting.

Bumblebees are half- to one-inch-long, yellow and black, hairy, stout-bodied insects that nest underground. There are usually fewer than 60 individuals per nest, which is usually built in an old rodent burrow or similar opening. Unless they present a problem, the nest should be left undisturbed.

For information, contact the local U. of I. Extension office or search the U. of I. Extension website at www.urbanext.uiuc.edu/bugreview.

Persons with an interest in monitoring bees, can go to the University of Illinois website, beespotter.mste.uiuc.edu, to participate in a statewide volunteer monitoring and photo recording program. The site also contains information on bee-friendly gardens, honey production, bee identification, solitary bees, colony collapse and other related topics.