Bees and Wasps Pest Control
These insects are important, some more than others.
Bees pollinate important food crops, and honeybees provide people with honey. Wasps, although we usually think only about their stings, are also beneficial. They kill large numbers of plant-feeding insects and nuisance flies and feed them to their young. In addition, both bees and wasps have important ecological functions. Because of bees’ and wasps’ many benefits, entomologists advise leaving them alone; unless their stings present a hazard. If bees or wasps are disturbing your picnics, or if a nest is too close to your home, there are a couple of things to remember. While they may appear threatening, many bees and wasps are not aggressive and will only sting when handled or stepped on. Most are beneficial to the environment and your garden.
Each species has different behavior. If you decide that the bees or wasps need to be removed, be careful! These pests sting and can be dangerous if you are allergic to their venom. So it is recommend to call a professional to remove them and their nests.
Yellowjackets (Vespula spp.)
The most common yellowjackets in the Northwest are the;
- western yellowjacket (Paravespula pensylvanica)
- The common yellowjacket (Paravespula vulgaris)
- Aerial yellowjacket (Dolichovespula arenaria)
- The German yellowjacket (Paravespula germanica) is becoming widespread in Washington.
Yellowjackets are about 1/2 inch long with jagged bands of bright yellow and black on the abdomen. The head and thorax are black with yellow spots and bars. They have a short, narrow waist and a broad abdomen that tapers off like a cone to a sharp point.
Yellowjackets are the most commonly encountered wasp species and are sometimes called the “meat bee” because workers scavenge for meat or sweets at picnics and around homes. Females can sting repeatedly. They will land on people who are nearby and crawl inside their clothes and are extremely defensive when their nests are disturbed.
Baldfaced Hornet (Dolichovespula maculata)
Baldfaced hornets are non-aggressive yellowjackets. They are about 3/4 inch long with black and ivory markings on most of their body. They can have nests close to human activity all summer without being discovered or being a nuisance. Full sized nests are about the size of a basketball. Nests are pear-shaped and completely enclosed by a “paper” covering. The cells in which the larvae live are not visible.
Baldfaced hornets’ nests are located above ground and can sometimes be removed without professional help. They will become agitated when the nest is moved or vibrated, so you must act swiftly. To avoid being stung, a professional should be called to remove the nest and hornets.
Paper Wasps (Polistes dominula)
Paper wasps are distinguished from yellowjackets by their long legs. They are one inch long, have distinct, slender waists. Many native species are golden brown with patches of yellow and red. The European paper wasp, first identified in the U.S. in 1981, has yellow and black markings that resemble those of yellowjackets.
Native paper wasps are less aggressive than yellowjackets and rarely sting humans, unless their nest is located near doors, a fruit tree, or some other place where people are active. In protecting their nests, European paper wasps are more aggressive than native paper wasps and are alert to movement up to 20 feet away. Typically they will not attack unless a person is very close.
Paper wasps hang their paper nests in protected areas such as under eaves, rocks, or tree branches, or in attics, exterior light fixtures and birdhouses. The nest hangs like an open umbrella from a stalk and has open cells that can be seen if you look up from below. The ends of the cells are open with the heads of the larvae exposed to view.
Paper wasps, like yellowjackets, die when the weather gets cold, except for the overwintering queens. Native paper wasps do not use nests for more than one season, while European paper wasps may occasionally use a nest from the previous year.
Paper wasps can be left alone in many cases. Around doors and other busy areas, it’s easiest to remove nests early in the season as the queen is starting to build her nest. The nest can be knocked down or hosed down. When nests are still small, they can also be vacuumed off at night when the queen and workers are home.
Cicada Killer Wasps (Sphecius speciosus)
Cicada killer wasps cause alarm because of their size and the stingless male’s habit of dive-bombing. Females reach 1 3/4 inches in length and males 1 1/4 inches. The western cicada killer is brown and yellow. Despite the threatening appearance, it’s difficult to provoke one of these wasps into stinging.
Cicada killers are solitary wasps, each having it’s own burrow. However, large numbers of burrows may be clustered together on favorable sites. Cicada killers prefer to burrow on dry bare soil, sand, flower beds, and areas with sparse vegetation. Females also excavate nesting chambers and then go cruising for cicadas. She brings back her prey and drags it down into the chamber to serve as food for her offspring.
Cicada killers do not pose a stinging threat, so control is seldom required. Their bothersome presence usually lasts less than two months. However, if wasp numbers are high or in a sensitive area, the following tips can help with control and prevention. Cover clustered burrows with a clear plastic tarp to prevent access and heat up the ground. In garden beds, a 3 inch layer of hardwood chips may deter nesting. Cicadas rarely burrow in dense, vigorous turf, so improve infested lawns by using appropriate liming, fertilization and watering. Mow high during nesting season.
Honeybees (Apis mellifera)
European honeybees are about an inch long with a black and reddish brown body covered with hairs. The female stings one time and then dies. Honeybees are usually not aggressive or threatening. Honeybees nest in many different kinds of places, but popular sites include inside chimneys or hollow trees, and in the walls of houses, barns, sheds and pump houses. Nests can also be found hanging from trees. The nests are made of wax cells. Honeybees keep their hives at 95 degrees, so you may be able to actually feel their heat through the wall. The entire colony lives through the winter.
Honeybees are liberal in where they decide to nest and are happy to make use of a variety of different kinds of hive sites. Never attempt to remove or destroy a honeybee hive, and remember that honeybees are beneficial insects and are not usually threatening. If you decide you must remove a hive, it is necessary to get professional help. Hives can contain a huge amount of honey and wax. Because bees keep their honey cool by fanning it with their wings, removing the bees means that the honeycomb can melt, attracting more bees and insect pests.
Africanized Honeybees (Apis mellifera scutellata)
The Africanized honeybee looks like a European honeybee, and like the European honeybee it stings only once. However, they are more defensive and less predictable. They defend a greater area around their nest and respond faster and in greater numbers than the European honeybee.
Welcome or not, these bees have made their way up from South America and are now present. They are more aggressive and more easily upset than typical honeybees.
If you live in an area where Africanized bees are present, prevent problems by using the following tips:
- Eliminate potential nest sites (abandoned vehicles, empty containers, anything with a hole, old tires).
- Inspect trees, garages, sheds, and fences regularly.
- Fill all wall, chimney, and plumbing- related gaps that are larger than an eighth of an inch.
- Cover rain spouts, vents, etc., with eighth-inch hardware cloth.
- To prevent children from being stung by Africanized bee stings, warn them to respect all bees, and notify an adult if they find a nest or swarm.
If you find a nest in or near your home, let professionals manage the problem.
Bumblebees (Bombus vosnesenskii)
Bumblebees have round yellow and black bodies covered with fine hair. They build their nests in the ground, under slabs, or in wall voids. They are not aggressive. However, the females can sting more than once.
Bumblebees are non-aggressive and can be good neighbors. Live with them whenever possible. If you must remove bumblebees, vacuuming is effective, or call your local Moore Pest Solutions expert.
Carpenter Bees (Xylocopa varipuncta)
Carpenter bees are large and round like the bumblebee, but are totally black with a bald upper abdomen. They are solitary insects and build nests in tunnels in dead trees or wooden buildings. They can cause some damage to poles or other structures. They are not likely to sting unless handled, and have a surprisingly mild sting.
Carpenter bees are valuable pollinators and rarely cause severe damage. Prevention tips to help manage carpenter bees:
- Fill depressions and cracks in wood surfaces so they are less attractive.
- Paint or varnish exposed surfaces regularly to reduce weathering.
- Fill unoccupied holes with steel wool and caulk to prevent their reuse. Wait until after bees have emerged before filling the tunnels. Once filled, paint or varnish the repaired surfaces.
- Protect rough areas, such as ends of timbers, with wire screening or metal flashing.