Wasps and hornets can put a damper on outdoor summer activities like picnicking, grilling, or enjoying a cool drink at the pool. These pesky insects like meat, fish, sweet beverages, baked goods, and are insistent on taking your food. Their sting can be painful and sometimes lethal, so be careful when they come near.
Only female wasps and hornets sting, since their stinger is an ovipositor, an appendage with which they lay eggs. Workers are all sterile females, so all are capable of stinging. Unlike bees, the stingers of wasps and hornets are smooth instead of barbed. Therefore, they can repeatedly sting their victims without dying.
In the spring, fertilized over-wintered females look for a suitable place to build a nest from chewed up wood and saliva. This can be in a tree, shrub, under the house or carport eaves, underground, or any protected spot. Check vent screening, and caulk areas where wasps are likely to get into the house, especially where the soffit and fascia meet under the eaves, warns Paul Wessner, general manager of All Natural Pest Elimination in Medford.
Entomologist Richard Siegfried, owner of Pacific Coast Pest Control, Inc. in Central Point, says the best way to control wasp and hornet populations on your property is to scout early in the year for queens that are starting to build nests and knock the nests down after dusk or early morning (the coolest time of day) when the queens are most docile. It is easier to destroy a small nest than to deal with a large one later.
Hornets and wasps become more aggressive as the summer ends, when their population in a single nest can number in the thousands. The slightest vibration of a lawn mower or sudden movements near their nest can cause an attack. Siegfried says one of the best ways of reducing their population later in the season is to use two wasp traps, one with tuna in oil and the other with fermenting fruit in it. This will attract the most wasps. A few drops of Bifenthrin or liquid Sevin mixed with the tuna and fruit will help control more insects, since poisoned food will be taken back to the nest for the larvae and queen. Remember to place lures away from your patio and activity areas and make sure that pets or children can't get access to the cans.
Another means of controlling these insects is to purchase a can of pesticide spray specifically for wasps and hornets, preferably one that can spray a long distance (20 feet or more). Follow the directions on the label and quickly leave the area after application. Underground yellowjacket nests are trickier to handle because you need to dig into the nest before you can adequately get the spray down into the area. Check for any activity the next morning. Repeat again after dusk, if necessary. If you don't feel comfortable doing this, or are seriously allergic to wasp stings, hire a certified pest control expert.
Wasps and hornets are beneficial because they eat a considerable number of destructive insects. If their nests are away from your family activities, don't harm them.
Discourage them from your property by picking up fallen fruit and keeping the lids on garbage cans secure. If a hornet or wasp comes near or lands on you, don't swat at it. Simply scoop it off with a piece of paper, a leaf or a handy object.
Until the first frost kills the workers, be increasingly aware of your environment while participating in outdoor activities. Follow these guidelines, and you'll be able to enjoy the warm days ahead safely.