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Nuisances Wasp And Bee Management

Overview

Stinging insects are limited to the order Hymenoptera, which includes wasps, bees, and ants. They generally do not sting unless handled, disturbed or harmed (when they feel threatened). Among 75,000 species of wasps and 20,000 species of bees worldwide, a few species are considered to be potentially hazardous insects, due to their stings. When they sting, they inject venomous fluid that creates allergic reactions to sensitive people. However, individual responses to a sting may vary from a brief swelling of the immediate area of the sting to a more severe, and potentially fatal, allergic response involving the entire body. It has been estimated that "about 200 people die annually in the United States alone from the reactions produced by wasp stings".

Wasps are nuisance pests in recreation locations, especially around picnic and garbage areas. They can also be a hazard to fruit pickers or workers where sweet substances are normally found or stored. Additionally, queen wasps are frequently encountered in Christmas tree shipments. Despite of beekeepers efforts, wasps impact honey production by reducing nectar and honeydew supplies for honeybees. Moreover, they attack honeybee hives in the spring to take away foraging worker bees. Later in the year, they also steal honey and carry off bee larvae and pupae. In this page, we are referring to the nuisance wasps and bees that nest in or around a structure. Beneficial, parasitoids, and other types of wasps and bees are beyond the scope of this document.

To make things easier, we categorized nuisance wasps and bees as either social or solitary insects. Adult solitary wasps and bees are all fertile and do not live in a colony structure. Whereas, social wasps and bees live in colonies and are distinguished with fertile queen, male and worker casts. Though, the majority of the colony is made up of sterile female workers. In order to protect ourselves from wasp and bee stings, we need to be familiar with their biology, habits, and management.

Facts

There are 4,000 species of wasps in the United States.
Social wasps live in colonies. In each colony, there are three castes: the egg-laying queens (one or more per colony), the workers, or sexually undeveloped females, and the drones, or males.
The paper like nest of social wasps (family Vespidae) consists of chewed plant material or wood pulp mixed with saliva and arranged in adjacent hexagonal cells.
Wasps and bees can nest inside wall voids and make a hole in the wall to enter or exit from.
Due to their barbed stingers, honey bees sting only once and die as they leave the stingers in the victim's skin. While wasps can sting more than once because they have lance-like stinger without barbs; thus they are able to pull out their stinger without injury to themselves.
Unlike the honeybee, wasps do not store food for the winter, and this is why their colonies only last for one season in temperate regions.

Identification

Social Wasps

Yellowjacket Wasps

Typical Yellowjacket wasps have black-and-yellow bands on the abdomen. The patterns of these bands help to distinguish different species. The workers are about 1/2-inch long, short and blocky, while the queen is larger, about 3/4-inch long. Depending on the nesting location, yellowjacket wasps can be classified as either aerial or ground nesting yellowjackets. Aerial nesting yellowjacket wasps (Dolichovespula spp.) usually build their nests in trees, shrubs, and on houses, sheds, and other above ground places; while, ground nesting yellowjacket wasps (Vespula spp.)

Construct their nests under the ground.

Bald-faced Hornet wasp (Vespula (Dolichovespula) maculata)

They are black with white to creamy marks on the front of the head and at the end of the abdomen
Heavy bodies about 7/8 inch in length
There is a signal queen in the nest
They are aggressive and sting repeatedly if disturbed
They make exposed aerial nests made of a paper-like material formed from chewed wood fibers mixed with saliva. Nests may reach 2 feet in diameter

Paper Wasps (umbrella wasps)

There are 22 species of paper wasps in North America and approximately 700 species worldwide
They are bout 3/4 to 1 inch long, reddish -brown with a yellow circle
They have longer legs and slenderer bodies than yellow jackets and hornets
Their abdomen taper at both ends
Their nests consist of a single exposed comb suspended by a narrow stalk resembling an inverted umbrella

Solitarily Wasps

Digger/ Threadwaisted Wasps

There are 20 species of digger wasps in the US and Canada
Adults about 3/4-2 inches long
They are robust and hairy with narrow waist
They are black in color with bands or areas of red, yellow, and/or white
Adults feed on nectar and feed their larvae on the paralyzed insects
Females excavate chambers in the ground. The chambers are supplied with paralyzed grasshoppers and crickets as stored food for their larvae. After the eggs are laid, larvae feed on provided food and grow to adults that emerge in the following summer

Cicada Killer

Large about 1-1/8 to 1-5/8 inches long
They have a black body marked with yellow across the thorax and on the first three abdominal (rear part) segments
The head and thorax are rusty red and the wings brownish
Legs are yellowish
Adults feed on flower nectar and sap exudates (any fluid that filters from the circulatory system into lesions or areas of inflammation)
Larvae feed only on cicadas
They prefer to nest in areas of thin vegetation, and rarely infest thick, vigorous turf
They overwinter as larvae in the soil. Pupation occurs in the spring and the adult emerges in mid-June to early July depending on the temperature conditions

Sand Wasps

They have stout bodies with pale greenish or yellow and black markings depending on the species
Adults feed on nectar and feed their larvae on insects (flies are the most common prey taken by these wasps)
Females dig holes to lay eggs in loose sand in a sunny position
Nests are short, simple burrows, with a single enlarged chamber at the bottom which is stocked with prey items for larvae
Females sting only when disturbed

Mud Daubers

They have long and slender bodies
They have a narrow and thread-like waist
Some species have a solid steel blue body (blue mud dauber), a shiny black body(organ-pipe mud dauber), or black with additional yellow markings (black and yellow mud dauber)
Females make nests from mud

Social Bees

Honey Bees

Beneficial insect (pollinator)
An adult honey bee is about 1/2 inch long and usually yellow, with 3 or 5 dark brown abdominal bands
They carry two pairs of wings and lack the constricted abdomen (wasp waist) of the wasp and hornet
They have dense hairs on the pronotum and sparser hair on the abdomen
Swarms of honey bees are usually seen in the spring "exposed swarms in tree branches, shrubs, signs, etc. are resting and probably will leave shortly"
Sometimes honey bees establish a new hive inside a wall cavity of a residential or commercial premises
The nests are made of wax cells that may contain many pounds of reserved honey
This wax will begin to melt in the warmer months, causing the reserved honey to seep out
This may or may not cause an unsightly damage, but it would attract other insects

Bumble Bees

They are large (3/4 inch long) with black and yellow or orange hair patterns on their abdomens
Queens and workers have pollen baskets on their hind legs
They live in a small colony (about 200 individuals)
Workers care for larvae produced by a single queen
Nests are generally found in open grasslands
Easily irritated stinging workers can respond quickly when their territory is invaded
Only fertilized females move to overwintering sites to survive the winter, while remaining workers, males and old queen die
In spring, bumble bees use old mice burrows, cavities in buildings, and other locations to start their nests

Solitary Bees

Carpenter Bee

Resemble bumble bees, but most of the top of the abdomen is without hairs and is shiny black in color
Female excavates a clean-cut, round entrance hole (3/8-1/2 inch wide) on or around the structure
Male and female overwinter as adults within their old nest gallery
Adults emerge in the spring (April and early May) and mate
There is one generation per year
Carpenter bees return to previously used galleries from year to year, although other bees can make new galleries as well

Halictid bees/ Sweat bees

They are about 3/16 to 5/6-inch long
They have black color with yellow, red or metallic markings
Nests occur in cavities in weeds or shrubs, or in the ground

Digger Bees-Anthophora sp

There are over 750 species of digger bees
They are large bees and can reach up to 1.18 inches long, very robust, hairy bees, with visibly protruding faces.
Make nests in the soil, either in banks or in flat ground
Although they are solitary insects, they many nest in large aggregations

Andrenid/ Mining Bees

There are about 1,300 species of mining bees in north America
They are about ½ inch long
Bodies are colored dark with fine light brown or yellow hairs
They tunnel into the ground to build nests

Colletid, plasterer, yellow faced or silk bees

They are a diverse group ranging from small, slender, relatively hairless bees (such as Euryglossinae) to large, robust, hairy bees (such as Diphaglossinae)
They burrow in ground, especially in clayey soil and line their burrows with a thin, clear plaster
The very common yellowfaced bees (Hylaeinae) resemble small wasps and carry pollen in their crops rather than on the legs

Leafcutting Bees

They are black, dark blue, purple or green covered with white, yellow, reddish or brown hair in color
Females nest in the ground, in logs, in hollow stems, twigs or wood siding
They cut semi circular plant leaf discs to construct cigar-like nests that contain several cells
Each cell contains a ball of stored pollen and a single egg
They are not aggressive, but will sting when they are handled

Orchard Mason Bees

They are good specialized pollinators on apple family trees (i.e., apples, cherries, plums, peaches, etc.)
They are about 1/3 inch long and blue black with a metallic sheen
The female uses existing holes (1/4 to 3/8 inches in diameter) in wood for a nest
The bee first places a mud plug at the bottom of the hole, then brings in 15 to 20 loads of nectar and pollen
A female lays an egg and then seals the cell with a thin mud plug
They like to nest in cavities or holes in sunny walls
They also like to use the weep holes found around windows and doors
Although they are solitary bees, mason bees are attracted to each other and build their nests in aggregations
Females have a stinger, but they use it only when they are in danger

Biology (Social Wasp)

During the late fall and early winter, as harsh weather approaches, newly mated/ fertilized queens seek protected habitats to spend the winter (over-wintering). Overwintering places may differ depending on the species. However, overwintering locations are normally located under tree bark, woodpiles, stumps and logs, and inside walls of structures. For example, the golden paper wasp, Polistes aurifer, is known to overwinter in wall void, crawl space, attic, chimney, basement, garage or window well of homes. In early spring, every queen will build a new nest. It will not use an old nest, but it may build a new nest on the side of an old nest. The storage of sperm inside the female queen allows her to lay eggs without need to mate again with a male wasp. Initially, the queen lays about 10-20 eggs. These eggs will develop into sterile females or workers that take care of the colony (raising, feeding, cleaning, fixing, defending and construction). Therefore, the queen's only job now is to lay more eggs.

By the end of summer, when the colony is mature and enlarged in size and number, males and new queens are produced in a large number to fly out and mate. Males die soon after mating; while, the new-mated queens seek protected areas for over-wintering, and repeat the life cycle. However, with the onset of cold weather, workers, immature stages and the original founding queen die. Usually, social wasp workers live for 12-22 days, and the average lifespan of queens is about one year.

Habits (Social Wasp)

Feeding habits: Wasps are very important pollinators. They feed on pollen and nectar from a variety of flowers. This helps moving pollen from one flower to another, and thus pollinates various crops. Besides pollen and nectar, adult wasps feed on sweet materials such as honeydew, fruit and other sweet resources. Female wasps have stingers that they use to subdue and capture prey such as insects or spiders to use them as protein food for their larvae. They also feed them on pieces of meat.

Nesting habits: Social wasps build nests of chewed up fibers or decaying woods mixed with saliva. The nests are usually found in sheltered areas outdoors in gardens, hedges, forest edges and other similar locations. Some species nest in the ground or at ground level in fallen logs and tree stumps. In urban settings, they can also nest under stairs, in fence posts, in brick walls, under eaves, under porches and in discarded mattresses, carpets or boxes.

Management

Trapping

Traps are more likely to be useful in small areas. But will not provide a satisfied level of wasp elimination
Use traps with bait "lure" to capture queens in early spring and late summer
Wasps change their food preference from meat to sugar; therefore, in the spring and early summer, wasps are attracted to protein-based baits; use jam or other sweet baits in later summer and into fall

Prevention

Early spring and late summer, block queen's entrances by sealing all cracks and crevices and apply wire screen in your windows before they build nests.

Remove fallen fruits, spilled food materials, drink sources, soft drink cans and garbage
Avoid scents and bright colors materials
Keep your house, dumpster, garage, attic, etc. clean

Nest Destruction/ Removal

It is advisable to wear protective heavy coverall clothing, leather gloves, helmet or bonnet with screen fitting veil or bee suit
Never disturb, squash and crush a wasp or bee, they will release an alarm pheromone that stimulate nearby nest-guards to attack by angry stings
In dark area, use red light "wasps cannot see red light"
To reduce risks to you and your family, contact your Pest Management Professional (PMP) to remove wasp nests

Chemical Management

A veil and protective clothing must be worn, especially if done during daylight hours.
The PMP will use an EPA approved fast knockdown residual insecticide (dust formulations are recommended or aerosol).
Treatment should be performed at night when temperatures have decreased, and when most of the foraging wasps are in the nest and less active.
Make sure that wasps are killed after treatment
Remove and destroy the nest, especially if the nest is built inside structural voids. If not removed, dead wasps inside the nest will generate unpleasant odor and attract dermestid beetles (hide beetles, larder beetles, carpet beetles, etc.) and ants (carpenter ants, etc) that feed on them.
For unexposed/covered nests, the last step should be sealing nesting areas. "Sealing the nest before making sure that all the wasps are dead can force survivors into the interior home".
Honey bees are beneficial, therefore, if they are encountered in or around a structure, a local bee keeper should be recruited to collect the honey bee colony alive if possible. But sometimes this approach is not practical as if the bee colony might have been established already inside a wall void. As aforementioned, this will create health and other problems to the people living inside the structure. Only in this case, the PMP will carefully use the same management methods described for wasps in wall voids.
In case of ground nesting wasps and bees, the PMP will treat all wasp burrows with an appropriate EPA residual insecticide (dust formulation is recommended). Homeowners should seal treated burrows after any night treatment.
Request product label & Material Safety Data Sheets (MSDS).
Follow precautionary measures provided by your PMP before and after treatment.

Frequently Asked Questions

Q: How are wasps different to bees?

Wasps do not collect pollen, bees do
Wasps do not store food, bees do
Wasps do not make honey, bees do
Wasp nests are made of paper, bees nests are made of wax
Wasp mouth parts are designed to chew food, bees mouth parts are designed to lap liquid
Wasps can sting more than once, bees can only sting once

Q: Why do wasps sting people?

A: To defend themselves, to subdue prey to feed their developing larvae or defend their nests

Q: How long do social wasps live for?

A: Social wasp workers live for 12-22 days, and the average lifespan of queens is about one year.

Q: What do wasps eat?

Invertebrates i.e., spiders and insects
Pieces of meat
Honeydew, pollen and nectar
Fruit and other sweet materials

Q: Do any other animals eat wasps?

A: Yes. Predators such as dragonflies, robber flies, true hornets, centipedes, birds and badgers

Q: How do wasps communicate?

Visual and audible communications- wasps use these kinds of signs for mating and defense purposes.
Chemical stimuli (pheromones) communications - these chemicals are used for maintaining the social behaviors and tasks of the colony members. For example queens produce a pheromone to regulate worker behavior and inhibits the development of their sexual organs. In case of danger, wasps also produce an alarm pheromone to provoke aggressive behavior towards an intruder.
Trophollaxic feeding communications- in this type of food related communications, the foraging worker wasps bring the raw food that they cannot digest into the nest and pass it to other workers to feed the larvae. In response, the larvae release a creamy drop of predigested materials that contains all necessary ingredients for the workers.