Bees in the Wall or Tree - What can be done?
Every year beekeepers are called upon to give advice regarding the removal of honey bees (and other insect pests) from homes and buildings. Such advice is difficult to give because each case requires first hand information, and no two responses are alike.
The following information is designed to give guidance about what needs to be done to accomplish honey bee nest removal and what considerations should be given when choosing a course of action. Properly completing a honey bee nest removal may involve a beekeeper to remove the insect, a carpenter to dismantle/reassemble the wall, and/or a licensed pest control company to eradicate the insects if removal is impractical. Keep in mind that you might also call an electrician or a plumber if safety or accessibility is an issue.
Although many of the observations and suggestions provided are specific to situations found in Michigan, much of this information is general enough that it would apply to any area of the United States.
Each situation is unique, so no set plan will solve all of the problems involved. Often, a great deal of coordinated planning is needed. Just remember that there is no Pied Piper of Hamlin that can wave a magic wand or play a magic flute to draw the insects out of their hiding place.
Honey bees are valuable pollinators. In the United States approximately 1/3 of our food crops benefit either directly or indirectly from honey bee pollination. The destruction of honey bees should be a last resort, if possible.
What should the homeowner do?
First, identify the insect. Identification of the insect or its nest can provide valuable information needed to assess the situation. The solution to the problem can be quite different for each species of insect that takes up residence your home. For example, bumble bees typically will not nest in a wall cavity, but often find suitable nesting in materials such as insulation, foam pads, and/or seat cushions. Yellow jackets will build their paper nests in wall cavities, holes in the ground, or in the attic (or crawlspace) of your home. Honey bees like the protection of wall cavities, especially in older homes that lack insulation between the wall studs.
Here are some tips to help you decide whether you have honey bees or some other insect:
If you see the insects flying from the entrance of the nest cavity in the spring (April to June in the north), then honey bees are a real possibility.
If you can find a dead insect, check to see if it is hairy. All bees have hairs while yellow jackets are smooth. You might take the insect to the Michigan State University Cooperative Extension office in your county for a positive identification. Pictures on the Internet or in insect identification books may be helpful in making a determination. There are a number of good yellow jacket websites, but we recommend Eastern Yellow Jacket.
If you can see any part of the nest, it may help with the identification. Honey bees build honeycomb out of wax. Other stinging insects use wood fiber to build paper nests, or they may use mud as a building material.
A licensed pest control firm may have the resources to help you identify your insect problem. There may be a cost for this examination.
You may find a beekeeper to help identify the insect in question.
Take a digital photo and send it to the SEMBA Web master, you can find his contact information here .
Removal of a yellow jacket nest
It would be helpful to review the yellow jacket's life cycle before you tangle with this insect. Knowing its life cycle and habits will help you decide whether to remove the insect and its nest or to simply live with it in your wall or in your yard.
Queen yellow jackets are raised in a paper nest beginning in the late summer to early fall. After mating, these queens leave the nest and find a protected location to hibernate. The old queen and all of the workers and drones of that hive will die and the paper nest will not be used the following year. Early the next spring, the new queens will come out of hibernation and seek a location to form a new nest. Depending upon the species of yellow jacket, some might build a paper nest on a tree, in a bush, or more commonly find a hole in the ground. Other species may seek out a cavity in your wall in which to build their paper nest. At first the queen does all of the paper nest making, egg laying and food gathering of nectar and insects for the young developing workers that are called brood. As the first brood hatch, they will forage for food, feed the young, and build more nest capacity. The queen will now stay in the nest to lay eggs. The size of the nest will increase dramatically by late summer and early fall.
Early in this life cycle, you will hardly be aware of the nest because it is so small and not aggressive. However, by late summer the numbers of yellow jackets will have increased tremendously and they will be more likely to sting anyone coming near the nest. (It is usually the yellow jacket and not the honey bee that will be attracted to your beverage can or other food that you are consuming out-of-doors.) The bald-faced hornet that makes a large paper nest has basically the same life cycle as the yellow jacket.
If you decide to eradicate yellow jackets, you could contact a pest control company or do it yourself. Locate the opening or openings and spray a wasp/hornet insecticide into the cavity opening. Evening is the best time because the majority of the insects are in the nest and not flying. Wearing gloves, a protective veil and clothing is advised. Follow the instructions and precautions on the label. It may take more than one application to completely destroy the colony.
If the nest is located in your home, do Not simply close up the opening because these insects may find a way into the living area of your home. Yellow jackets that come into the home are usually not aggressive and often will be found at the windows looking for a way out.
If the location of the nest is in an area (up high for example) where they are not bothering anyone, you might consider just leaving them until cold weather when they will all die. Then the important next step is to seal up the nest openings and look for and seal other places where insects could enter the following year.
The inside of the nest of the yellow jacket and bald-faced hornet is very interesting. Use due caution when letting your children take the nests to school for show and tell. More than once, one or more un-hatched insects have emerged and interrupted a classroom.
Removal of bumble bees
The life cycle of the bumble bee is essentially the same as yellow jackets, hornets and wasps with only the fertile queens surviving to start nests the next year. For additional information on bumble bee biology and control visit: www.doyourownpestcontrol.com/bumblebees.htm
The same wasp/hornet spray recommended for yellow jackets will kill bumble bees. Evening application works best. Bumble bees can be very aggressive when disturbed so use protective clothing and carefully follow the instructions and precautions on the label. Again, several evening applications may be needed. If you should choose to leave them, wait until cold weather, remove the old nesting material and make preparations to close off any entrances that newly hatched queens might enter next spring.
Like the honey bee, the bumble bee is an important pollinator. If you can live with a bumble bee colony, you might want to let them benefit your property.
Removal of honey bees
Dealing with honey bees is a more complex issue and the degree of difficulty is much greater. The first step in the process is to identify exactly where the honey bee colony is located in your home. Then get ready to go to work.
In recent years, several pest control companies have decided not to be involved with honey bee removals. In fact some firms will tell the landowner that it is illegal to kill honey bees. Often they argue that there is a shortage of honey bees, that honey bees are protected, or that they cannot do removal without a permit from the Michigan Department of Agriculture (MDA).
The truth of the matter is that removal of honey bees from a home is a matter of personal safety, and there are no rules in Michigan that would prevent a landowner from removing a colony from their home. The information from pest control companies is simply not correct.
Michigan's State Apiarist, Mike Hansen, routinely explains to homeowners that there are limited numbers of beekeepers interested in collecting nests from homes because the time and effort is seldom worth the prize. In regard to shortages of honey bees, there is a shortage of feral honey bee colonies (wild bees), but beekeepers have sources for purchasing replacement bees. A beekeeper can purchase honey bees more economically from firms that raise the line of bees that the beekeeper wants. Beekeepers also have the ability to increase the number of their own colonies by splitting the ones they have.
The shortage of feral colonies of bees has been caused by the unwanted introduction of honey bee pests during the last 20-25 years. The tracheal and varroa mites, as well as the small hive beetle, can devastate a wild colony because there is no beekeeper to apply the products needed to protect these colonies.
There may be some confusion in the pest control industry because there is a requirement on all agricultural pesticide products that is intended to protect managed colonies of honey bees from pesticide drift or misapplication. Since farmers need honey bees to pollinate their crops, there is little argument that honey bees need to be protected in the agricultural setting.
You will seldom see this requirement on products that you can purchase at the local hardware store, or even on the labels of products used by firms that spray for insects in and around your home. It appears, however, that the precautionary statements on agricultural pesticides is being misapplied by pest control companies.
Hansen reports that he checked with his State Apiary counterparts from the Apiary Inspectors of America (AIA) and with apiary officials from the USDA several years ago, and there is no 'Federal Protection for Honey Bees' as the pest control firms have stated. What we have here is what's known as an "Urban Legend."
Dealing with the problem
Before we outline the methods of honey bee removal or eradication it may be helpful to review some information about the honey bee nest in your wall.
Why did the bees choose this wall?
When honey bees reproduce in the spring, they can quickly become over crowded. This activates a natural event called swarming wherein about one half of the bees in a colony will leave with the old queen to search out a new home. In the old established hive new queens will hatch, mate with drones and begin laying eggs. The old queen will fly a short distance from the hive and land. Attendant bees will cluster around her forming a large mass called a swarm. Scout bees will leave the swarm and search out a cavity to form a new nest. This new cavity could be in a tree, an old barrel, a cavity in a wall in your home with an opening at least 5/16 inch, or they could (in a rare situation) build an exposed nest on the side of your home or on vegetation. If the cavity in your wall had bees before and the opening was not sealed, the odor of the wax comb may attract them to that location.
Could I have prevented bees from occupying my wall?
Yes, if you had sealed all holes 5/16 inch or larger that led to a cavity.
What does the swarm do inside the cavity to make a honey bee nest?
When honey bees move into a cavity, they first build wax comb cells and begin to fill some with nectar (this later becomes honey) and pollen. The queen will begin to lay eggs in other cells. After 3 days, the eggs hatch and become larvae feeding on honey and pollen. After 9 days of feeding, larvae become pupa then adults. This cycle (from egg to adult) takes 21 days. In a recently established hive, the amount of comb and brood (immature bees) will be small. The average swarm contains about 10,000 bees. A more established hive may have wax comb filling up the entire space 16" x 4" x 7-8 ' between the studs and may contain 50,000 to 60,000 honey bees. If the wall becomes too warm, especially on the south side of the building, the wax may melt and the honey may flow down the wall. An active hive keeps the hive cool enough so this seldom happens.
What safety concerns should I be thinking about?
You should be concerned if someone living in the house is allergic to honey bee stings. Only a small percentage of people are allergic to honey bees; but for these people venom can be life threatening. Honey bees sting to defend their colony. Avoid walking in front of the entrance and avoid any disturbance near the hive. When bees leave the entrance, they usually fly upward. If the opening to the nest is higher than 8 to10 feet walking by will cause little disturbance.
Should I plug the hole?
You could, but don't! Bees will look for another exit which could include holes leading into your home; your house has several openings like those around ductwork, or ceiling and wall fixtures. You don't want the bee's only route out to be through the inside of your house.
Can the bees be saved?
Sometimes bees can be saved by trapping them out of the wall or by physically removing them after dismantling the wall covering. Both procedures are time consuming and costly and most beekeepers are not interested in providing this service. The value of the honey bees to a beekeeper is minimal as the survival rate for bees removed physically (cutting out comb, etc.) is poor.
If there is no immediate threat, what is the best time for removal?
Late winter/early spring is a good time because the bees have consumed a large amount of their stored honey during the winter. Also, the number of bees present in the hive is lower than it will be later in the spring.
If I can find a beekeeper to remove them what is involved?
The ideal situation for removal of honey bees would be in the late winter/early spring and where the wall is easily dismantled exposing the comb and contents. The homeowner must pay the expense of dismantling the wall and having the wall rebuilt. The comb with brood and honey is cut out and placed in frames to be placed in the beekeeper's hive box. Some beekeepers use a special vacuum that will remove bees from the exposed comb without killing them.
Often the situation is not ideal because of the kind of building material (brick, cement or stone), the location, or some other factor that presents an obstacle.
Before you call a beekeeper for assistance, you should be able to answer the following questions:
What kind of insect is nesting in your wall?
Are the insects an immediate danger to people or animals? Has anyone been stung? Is the entrance in the wall near a place where people must walk?
How high is the entrance? Is there more than one entrance?
How long have they been there?
What is the wall construction material?
What direction does the wall face?
Options for removing or eradicating bees from walls
So, what are your options? In our opinion here are your choices.
Just leave them alone unless safety is a concern. Homeowners often follow this advice. In many cases the unmanaged bees will die over the winter due to problems with disease, parasitic mites, starvation, prolonged cold weather and other conditions. If you are convinced that the bees are dead, be sure to seal that opening as well as other places where bees may enter.
Contact a pest control company for assistance. You may need to call several before you find one that will eradicate honey bees. Expect that eradication will not be a simple task and the charges for these services will reflect the difficulty of the job. It has been our experience that a single treatment kills only the adult bees flying or walking around the nest. After a few days the pupa, protected by the wax of their cells, will emerge as adults, so you still have a problem. We recommend that you insist they treat at least 2-3 times over a two week period.
Find a beekeeper that will physically remove the comb and bees after the wall is removed exposing the nest. Expect to pay the beekeeper because the value of the bees is questionable at best. The labor needed to remove the colony coupled with angry bees and sticky honey makes this job difficult. When the beekeeper is done, you still have to rebuild the wall.
Here is a list of beekeepers in the Southeastern Michigan area willing to do this work:
- Don Schram, Waterford -- 248-310-8205
- Michael Sautter, Allen Park -- 313-383-4595 or 313-220-7729
- Richard McFarland, Marine City -- 586-212-1476
- Mazin Malallah, Romulus -- 313-999-3180
- Bob Dluzen, Petersburg -- 734-279-2743
- Judy Durfy, Ann Arbor -- 734-302-5396
- John Kustra, Plymouth -- 734-233-5374
Some beekeepers have saved bees by trapping them from the wall. Essentially, trapping involves reducing the entrance to one opening and installing an exit cone. The cone is usually screen wire shaped into a funnel-like design. The base is secured over a single entrance. A small exit at the tip of the cone, no larger than 3/8", allows the bees to exit but they cannot re-enter. The beekeeper places a small hive with a few frames of brood, honey and a queen (this is called a nucleus or "nuc") near the exit cone. Bees that leave the nest in your wall will then join the "nuc". Depending upon location, height, etc., a scaffold, ladders, and devices may be required to hold the "nuc" in place. The size of the nest in your wall will determine how long it takes for all the bees to complete the exit. We have found that it can take up to two months in some cases. It works best by starting early in the spring when the colony is small. Other details on trapping techniques of trapping can be found in beekeeping publications.
Eradicate them yourself. Aerosol pesticides, containing pyrethroids labeled to kill wasps and hornets can be used and are effective because they kill the insect immediately on contact. For best results, wait until evening and spray into the opening/openings. If you can locate the actual location of the colony in your wall, you can drill additional holes through which to apply the insecticide. You may have to spray every two to three days. Spraying is less effective if the nest is located far inside the wall away from the opening. It will take longer if the nest has been there for some time. When you first spray, the un-hatched developing bees (pupa) are protected by wax comb; therefore, you may have to repeat the process again in two to three weeks. After determining there is no more activity, seal all holes that could attract future invaders.
Other insecticides like Sevin in a dust formulation may be applied using a gas motor or electric blower, modified with a small opening, to force the dust into the nest. Bees will not die immediately but will track the dust throughout the hive causing eventual death. Some have used a garden hand-duster dispenser to introduce the dust into the nest.
It is important to follow label instructions and safety precautions. When using a pesticide application, follow all of the precautionary statements on the label to ensure that you don't harm yourself. Clothing worn when making an application should always be washed separate from the normal laundry. Always make sure the pesticides you use are properly labeled for the job at hand, and follow the directions.
In each of the above cases, it's important to determine where the nest was located. Honey and wax that is not kept cool by a colony of honeybees can melt and seep through your walls. The smell of honey and wax left behind by a colony is also a calling card to new swarms. If you don't take the precaution of carefully sealing your wall, you can quickly have another colony take up residence in the same place. If the colony is large, tear out the wall, clean up the wax and honey, and paint over the area. Remember that it's cheaper to replace a sheet of drywall from the inside of the house than it is to replace the outside of the wall.
Bees in a tree what can be done?
One of the most common nesting sites that honey bees choose after swarming is a hollow cavity in a tree. When the honey bees that were brought to America in skeps in the 1600s they swarmed and located in hollow cavities in trees. It is estimated that these bees moved from the east coast westward at the rate of 50 miles each year.
In these tree hives, the entrance to the nest is often located high in the tree where the bees remain unnoticed for years and usually do not cause any problems. But if the tree is blown down or if the entrance to the hive is low, the flight path of the bees often interferes with human activity. This is when the owner calls upon a beekeeper to remove the nest without killing the bees. Saving honey bees that have formed a nest in a tree cavity is very difficult and it should be noted that the bees themselves are of little value to a beekeeper because of the time and work required to do the removal.
So what choices does the owner have? 1) Continue to live with the bees in the tree. 2) Cut the tree down, cut out the section housing the nest and have a beekeeper split open the section. The exposed comb, brood and bees can then be transferred to a hive box. Early spring is the best time for this removal procedure so that the bees have enough time to build up for winter survival. 3) Move the entire tree section to another location, stand it upright, make a opening in the top of the tree nest and place a hive body on the top so the bees will move up to relocate in the box. 4) If the tree can't be cut, find a beekeeper who could place an escape cone made of 1/8" hardware cloth over the entrance and place a hive body with a small colony of bees close to the escape. The escape allows the field bees to come out of the tree hive, but not back in while the queen and house bees remain in the nest. The trapped out bees will join the outside hive body. This procedure will take several weeks. If you go to Google and type in one way trap for bees there are several videos showing the construction of a one-way trap.
If a beekeeper is asked to do any of these procedures expect to pay for this service. The work and time involved probably is not worth the effort financially. Even though most of us hate to kill bees, the practical decision would probably be to exterminate.
If you choose to exterminate the honey bees, you will find very few professional exterminators who provide this service. To exterminate them yourself, apply an insecticide powder or spray into the hive opening over a three week period. The first application will kill the flying bees but not the unhatched bees which are protected by wax coatings, thus the need for several applications of insecticide. When the worker bees and queen die, there will be no new bees hatching and the entire nest will perish.
We hope this information will assist you with this difficult problem
Roger and Mary Sutherland
5488 Warren Rd.
Ann Arbor, MI 48105
Michigan Department of Agriculture