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The honey bee, Apis mellifera, is our most beneficial insect. We must do all we can to protect bee colonies, which contribute as pollinators for many of our fruits and vegetables. The annual contribution of honey bees to food production in the United States is estimated to be $10 billion. Honey bees are primary pollinators of almonds, apples, blackberries, blueberries, cantaloupes, cranberries, cucumbers, forage crops, kiwi fruit, squash and watermelons. Annual cash receipts of South Carolina commercially grown apples, cantaloupes, cucumbers and watermelons are estimated at $25 million.

In South Carolina, we have about 2,500 beekeepers. They manage about 30,000 honey bee colonies that produce 1.2 million pounds of surplus honey annually in addition to the pollination service, which many people take for granted.

We should do everything possible to salvage honey bee colonies that become a problem in structural walls, but there are many instances when this is not possible. If a local beekeeper cannot be found to take the bees, the property owner has every right to treat honey bees as pests, especially when human safety is involved. Some basic knowledge of honey bees and their activities is necessary before attempting to remove honey bee colonies from structures:

• Honey bees will defend themselves or their colony if threatened. Avoid disturbing a bee colony unless you are fully protected. If you encounter bees that are flying and appear to be out of control, simply walk away slowly without swatting at the bees. Swatting the bees only irritates them more. If you find yourself being attacked by bees, cover your head with your shirt and run quickly through dense vegetation or seek shelter in a vehicle or building.
• The guard or worker honey bees have a barbed stinger that is left behind in the victim. While stinging, a honey bee rips a portion of her abdomen away with the stinger, and the bee dies soon afterward. The stinger should be removed immediately from the victim to reduce the amount of venom entering the sting site. A preferred sting remedy is to place a mound of common table salt on the point of sting entry and dampen with water. By osmotic pressure, most of the venom will be withdrawn from the body tissue if the treatment is applied within three to four minutes following the stinging incident. When working outside, it is advisable to carry small amounts of salt such as the packets found at fast food restaurants.
• Honey bee swarming season normally occurs in South Carolina during the months of May and June, although there are exceptions. This is the time of year when swarms may enter the wall of structures and become a pest problem. A swarm will enter a void or cavity that averages about 10 gallons in size. Normally, honey bees favor a cavity entrance that faces southeast and is about 1.5 inches in diameter.
• A mature honey bee colony contains 20,000 to 100,000 bees, depending on the season. The population will peak from late spring to summer and reach a low point in winter.
• A European honey bee colony will swarm normally once a year, whereas an Africanized colony will swarm several times annually. Swarms occur in spring during strong nectar flows when the colony population outgrows its living quarters. The old queen and about half the bees will emerge from the parent colony to find a new home. The parent colony has made preparations to replace the old queen prior to swarm emergence. When the swarm emerges, the bees will cluster on a nearby tree limb or other object and remain there from an hour to sometimes 24 hours. Scout bees are dispatched to search for a new home for the swarm while the queen and remaining bees await their return. The swarm will fly in a group to the new home described by the most convincing scout bee. The new home may consist of a hollow in a tree, a vacant beehive, an abandoned water heater, a cavity in a wall of a structure, or any other void that meets the specifications of the scout bees.

If a property owner suspects that a honey bee colony has entered the wall of a structure, he/she should attempt to confirm the insects are indeed honey bees. Other possible insects that might invade the wall of structures are carpenter bees, yellow jackets or European hornets. Honey bees vary in color from yellow to black, have black or brown bands across the abdomen and are much smaller than a carpenter bee. Honey bees are about ²/3 inch long and covered with hairs or setae. The foraging honey bees have pollen baskets on each hind leg, which will often be loaded with a ball of yellow or dark green pollen. The honey bee is the only stinging insect that can normally overwinter as a colony inside the wall of a structure in South Carolina.

The carpenter bee can be identified by having bright yellow, orange or white hairs on the thorax (chest region) and a black shiny abdomen on the dorsal side. Carpenter bees are robust, heavy-bodied bees that range from ¾ to 1 inch in length. These insects bore ½-inch diameter holes that appear to be perfectly round on exterior wooden surfaces.

Yellow jackets lack the dense body hairs that are found on carpenter bees and honey bees. Yellow jackets do not have the pollen baskets on the hind legs. The yellow jacket is about ½ inch long, and the abdomen is characterized by having alternating yellow and black bands. European hornets are much larger (1.5 inches long) than honey bees and sometimes establish colonies inside structural walls.

NOTE: The property owner must first decide whether to seek out a professional to do the job. Some beekeepers are experienced in honey bee removals and will remove the bees for a fee, but sometimes a carpenter will be needed to assist in reconstructing the wall. If you do not know a local beekeeper, call your Clemson University Cooperative Extension office, which may have a listing of local beekeepers. Also, some pest control companies have employees who are trained in bee removal.

The honey bee colony should be salvaged alive if possible, but sometimes this is not practical. Honey bee swarms that have recently entered the wall of a structure, say for a day or so, can often be exterminated by injecting a pesticide recommended for bee control into the cavity. The bees should not have had time to construct a significant amount of comb, produce much brood or store much honey unless a very strong nectar flow is in progress. Remember that if the bees have stored much honey in the wall and you kill the colony with a pesticide, the honey will be contaminated with the pesticide. Foraging bees from another nearby managed or feral bee colony will be attracted to the honey in the wall and may cause other unnecessary colony demise. To avoid this problem, caulk or place window screening on all potential entrances to the wall cavity. This will prevent another swarm from entering the same cavity the next swarm season. A foul odor is to be expected for several weeks in the vicinity of the decaying bees if removal is not conducted.

Once the bees have set up housekeeping for more than a few days, the job often becomes more difficult. Sometimes, much comb (beeswax), brood and honey are stored in the wall of a structure. Simply injecting a pesticide in the wall to kill the bees is risky. The comb will attract wax moths and mice. The honey will attract ants and other insects and may ooze through the wall or ceiling when comb melts during hot weather.

A process called "neutralization" is necessary to get the job done right and avoid future problems. To prevent future infestations, neutralization involves the complete physical removal of all bees (dead or alive), comb and honey from the wall following extermination. The removal process should be scheduled when no humans or pets are in the immediate area. A good wash down of the cavity with soapy water is recommended to remove all odors of the previous colony. If possible, it is a good idea to leave the void area open for a couple of weeks to allow drying and dissipation of colony odors. Filling the void with spray foam insulation or fiberglass batting prior to wall closure will prevent re-colonization of the space.

Depending on the exterior wall construction, the neutralization process may have to be conducted inside the structure, although exterior wall removal is preferred in most cases. The dimensions of the wall space occupied by the bee colony can normally be investigated in late evening by careful heat and noise observations. A stethoscope is a handy device to have when inspecting the size of the colony. An outline of the colony can be identified by carefully listening for a drastic decrease in the buzzing sound created by the bees. A light tap on the wall surface with a screwdriver or hammer will elevate the noise intensity.

A list of suggested equipment needed to salvage a bee colony alive from a structure wall is listed below:

Most of the equipment listed above can be purchased at hardware stores, but the specialty equipment for working around honeybees cannot be found locally in many areas of our state. A few South Carolina beekeeping supply dealers can be found in the yellow pages, or you may want to ask a beekeeper for references. Two beekeeping supply mail order companies that will send you a free catalog are listed below:

Removal of established bee colonies from structure walls can be made more pleasant by scheduling the job during the time of year when bee populations are low, a minimum of stored honey is present and the bees are less defensive. Early spring before the nectar flows have begun is the best time of year for bee removals in South Carolina. Another preferred time of year is late fall or on a mild winter day.

Another suggestion for bee removal from a structural wall is to remove parts of the exterior wall and disrupt the colony during extremely cold temperatures. Honey bees cannot fly during freezing weather and the bees will normally die from exposure. The neutralization process can be completed much quicker during cold temperatures. REMEMBER: Although bees might be unable to fly in cold weather, they can sometimes crawl and sting. Observe the same safety precautions when working with bees in cold weather or warm.

Exterior stucco, brick or cement walls make normal removal impossible, especially if interior wall accessibility is not an option. Trapping bees out of the wall with a "one-way bee escape removal" is recommended if a property owner is not in a hurry to have the colony removed. The process will take about two to three months, and sometimes it is not successful unless careful attention to detail is followed. The comb will remain in the wall and will attract another swarm in the future unless preventive measures are taken.

The cone-shaped one-way bee escape is constructed of window screen with the large end fastened over the primary bee entrance. It is imperative that all other cracks or holes leading to the bee colony be sealed off, or your efforts will be unsuccessful. A hive body with a new queen bee inside is placed on the platform with the entrance as close to the primary entrance as possible. Returning foraging bees will fly to the base of the cone-shaped bee escape and will be unable to reenter the wall. Eventually, the foraging bees will successfully gain entrance to the adjacent hive. Periodic checks to make sure the bees have not gained entry into the wall are necessary. As the colony in the wall weakens, the colony in the hive body will strengthen at the expense of the parent colony. The queen in the parent colony will not normally abandon her brood, so a non-residual pesticide or carbon dioxide should be injected into the wall to kill her and the remaining bees. Make sure the fumigant used does not leave a toxic residue. After four to five days, the cone escape can be removed and the bees from the new hive will enter the wall and remove the remaining honey. As soon as bee entry into the wall ceases which should only take a few days, all possible entry sites must be sealed or plugged to prevent re-colonization by future swarms. Filling the void with an expanding foam type of insulation is highly recommended.

Unfortunately, this trapping procedure requires many visits to the site to finish the job. The comb left behind in the wall will be highly attractive to scout bees in the future, therefore the structure owner should make annual inspections of the wall and refill any cracks or holes leading to the cavity.

One percent of the human population is allergic to bee stings. These individuals should take every precaution to avoid bee stings because one sting can be immediately life-threatening. An available prescription sting kit is highly recommended for these individuals during outside activities.