If you find a nest on your property and think it might belong to either a bee, hornet or wasp colony, it is important to consider the risk t...
Case Studies
My dad hated all stinging insects, and especially those that built nests under the eaves of his barn. Every year, he'd get a ladder and aerosol can of pesticide and spray nests. After he got chased down the ladder once too often, he rigged up a spray can at the end of a 10-foot-long piece of conduit. Armed with this can-and-pole device, Dad eliminated everything.
That scorched-earth approach was based on what he thought was potential harm to his kids and farm animals. And for people allergic to stings, bees and wasps do pose a serious health concern with sometimes fatal results.
But what if allergic reactions are not an issue? Don't bees, wasps and hornets serve a purpose in the ecosystem? How do you control the ones with stingers without killing all of the beneficial insects?
The differences between hornets and wasps are easy to see and control depends on the critter. You first have to know what you're looking at. Wasps and hornets have very different appearances and behaviour patterns. Wasps are slow flyers that travel with their rear legs down and have thin waists. Hornets are dramatically different – they have a cigarlike shape, and they fly like jet fighters.
In the UK, the two main problem species are the European wasp (Vespula vulgaris) and the common hornet (Vespa crabro). They are commonly referred to as "meat bees", but they aren't in the same family as the honey bee and shouldn't be confused with wasps that build paper, open-celled nests.
Wasps are aggressive insects building hives under or near the ground and feeding on both live insects, dead animals and nectar. They are the ones that land in fizzy pop cans and bother you during summer barbecues.
As their name suggests, paper wasps build large paper nests in trees or other high places (such as the eaves of your house). These nests are round or oval shaped and can grow to be about the size of a football. They feed exclusively on live insects such as ants, caterpillars, aphids, flies and mosquitoes.
From May until late June, all wasps are predators on other insects. You will find them flying around in the garden collecting food and helping to control harmful insects. Later in the season their diets change to include meat and other foods. Typically, this is a result of supply and demand because the number of insects goes down. Most of the time, wasps won't harm you if they're left alone.
When their nest is disturbed, wasps will swarm out and attack. If you find a wasp nest, be careful not to disturb it.
Paper wasps (Polistes dominulus) have a similar colouring to the common wasp, but they are generally docile and don't cause problems. Females are solitary and build small nests from paper. These nests often appear along the eaves of homes during summer months. They are papery, 2 to 4 inches across and have a honeycomb appearance when viewed from below.
Before you remove any nest, decide if the residents are really causing you problems. If you have an aerial wasp nest on the second story, or 30 feet in a tree, we'd probably encourage you to leave it.
With wasps, the best choice might be noninterference. This species almost never stings humans, and they're very docile and nonaggressive. If you have a nest over the door, you might remove it. Otherwise, we'd probably not recommend control.
The bottom line should always be value versus potential danger. Before you remove any nests, consider how beneficial they are. We really need these guys if you want to go green.