Why are yellowjackets so bad in late summer?
Because their colonies are at peak size. WSU says colonies start from a single spring queen and peak near the end of summer, with August to September the most troublesome and the German yellowjacket largest from October to early November. Workers also switch from hunting insects to seeking sugar, which brings them to people.
That change in diet explains why a calm June turns irritable in August. Soda cans, fallen fruit, barbecue scraps and open garbage all attract them. Cover drinks, empty bins and clear windfalls from under trees.
Because colonies are annual, nests die in the cold and are not reused. Mated queens overwinter under loose bark or in protected places, and the cycle restarts in spring.
Should I try to remove a nest myself?
Not if it is near people. WSU recommends professional removal for nests near where people live and advises against swatting. About one to two percent of people are severely allergic to stings, so a nest near a door, deck or playground is a safety matter. A small, open, inactive nest can be handled with care.
Do-it-yourself sprays can fail to reach the nest, and an angry colony may defend itself. Disturbing a ground nest with a hose or a shovel is especially risky.
If anyone has had a severe reaction, such as swelling of the throat, trouble breathing or widespread hives, treat stings as an emergency and call 911.
How do I tell a yellowjacket from a bee or a paper wasp?
Yellowjackets are smooth, black and yellow wasps that nest in the ground or in voids and scavenge at food. Bees are fuzzy and rounder and are not treated as pests to eradicate. European paper wasps build open-comb nests on structures and are common in cities, according to WSU. A technician confirms the species.
The nest is the best clue. A paper nest with an open honeycomb of cells under an eave suggests paper wasps. A hole in the ground with a stream of wasps suggests yellowjackets. A ball-shaped grey nest hanging from a tree may be a hornet, covered on hornet nest removal.
Do not guess when bees are in question. Honey bees are often protected by local beekeepers, and a technician or a beekeeper can advise.
Can I prevent yellowjackets around the house?
Partly. Keep food and drinks covered outdoors, use tight-lidded garbage bins, clear fallen fruit and seal gaps in siding and eaves in spring. These steps make a property less attractive but cannot stop a queen from nesting nearby. Check eaves and sheds in spring for early nests.
A tiny nest started in spring is easy to deal with. By August it is a major job, so a quick look in April and May is time well spent.
If you find a small early nest, ask for advice before disturbing it, especially if it is in a wall or the ground.
