They may play a big part in pollination. And sure, they help to eliminate nuisance insects. But no matter: ask anyone what they think of wasps, and the answer is fairly unanimous and spontaneous. Not in my backyard, please!

Generally speaking, people are afraid of wasps because of their painful stings. Anyone who has inadvertently wandered too close to a wasps’ or hornets’ nest has most likely had the displeasure of getting a taste of their venomous medicine. And we can all do without their bothersome aerial ballet while trying to enjoy a meal out on the deck.

Thankfully, there are steps you can take to avoid having too many wasps as company this summer.

Nests come in all sizes
In a ritual repeated every spring, mated queens leave their hibernation sites. Each is in search of a new home for her colony, which will eventually become a nest. There are three main types of wasp nest in Quebec:

  • The smallest is about the size of a hand and looks like an upside-down umbrella. These nests are usually found hanging from branches or eaves, and can accommodate 15 to 200 paper wasps (the genus Polistes), which are not particularly quick to sting either humans or animals.
  • Other nests are hidden—in a hole or depression in the ground, or a dark place in a building (inside a wall, attic or shed, or under a balcony). They are home to the nastiest wasps: yellow jackets, or Vespula. These are scavengers who will promptly and aggressively go after food on your plate.
  • The most frequently seen nests are also the largest, with room for up to 5,000 wasps! They may be yellow jackets (Vespula), but could also be hornets (Dolichovespula), which are not very aggressive. Eaves, porches and trees are the most likely sites for these nests.

Don’t set the table for them
The main reason wasps leave their nest is to find food. The bigger the population in the nest, the more wasps will come and go. As summer progresses, more and more of these wasps will show up uninvited at your outdoor table, especially if it is laden with drinks, sweet foods or meat, all of which they find irresistible. The best defence is therefore to keep all food in covered containers.

Similarly, make sure all table scraps wind up in a covered garbage can. Also, pay particular attention to recycling bins in which you have discarded wine, juice or soft-drink bottles. Any of these containers is extremely attractive to wasps, and must be kept well away from high-traffic areas—for example, children’s play areas.

Taking the sting out of things
It’s not such a good idea to buy funnel-shaped wasp traps, precisely because they contain bait that tends to attract a lot of wasps! Also, never go near a wasp nest if you can help it, especially in late summer. If a wasp is circling around you or lands on you, don’t make any sudden movements. Gently wave the wasp away so as not to scare it; if a wasp is attacked or crushed, it immediately releases a chemical alarm that attracts other wasps to the same spot. You should also keep in mind that a wasp can sting the same target more than once, because, unlike a bee, it can easily withdraw its stinger.

Operation: Destroy
What if you’ve located the wasps’ hideout? If you find a nest in an area where it poses no risk, it’s best to leave it where it is until it has been abandoned (usually by November or December).

If the nest does pose a risk to humans or pets, keep in mind that it is always best to call in a professional exterminator. Early spring, of course, is the least dangerous time to deal with a nest; the job becomes riskier as the nest becomes larger.

If you do try to remove a wasp or hornet nest yourself, this is best done at dusk, and you must wear protective gear including a net covering your head. The operation requires completely enclosing the nest in a plastic bag, detaching it, and then sealing the bag. If you need to use a flashlight, make sure it is not overly bright, and use a red filter over the bulb to avoid alerting the wasps.

References: Montréal Insectarium www2.ville.montreal.qc.ca/insectarium/toile/nouveau/preview.php and www2.ville.montreal.qc.ca/insectarium/gareaudard/site_en/index.html.