[Pest Spotlight] Social Bees & Wasps

No one gets stung on purpose unless, of course, they’re into some offbeat type of research. Bees, wasps, ants and scorpions don’t necessarily pay any attention to pest professionals until they’re disturbed. A professional can lose all sense of propriety should fire ants find their way inside his pants or hornets literally begin breathing down his neck.

Stinging pests can pose a risk, though usually small, to all pest professionals during the warm months of the year. Training your staff now will pay big dividends next spring.

Avoiding stings depends on following a simple rule: Be alert! Accidental stings most often occur because one becomes focused on the task at hand and fails to notice other things around him. When faced with the knowledge that a yellowjacket nest already exists under a shrub, a professional can take the necessary precautions by staying clear of the area or by wearing a bee suit. It’s when a professional is searching under the shrub for something else, like an ant nest, that the wasps surprise him and stings occur.

Fortunately, most people are not severely or even moderately allergic to insect stings. A few, however, can have their lives threatened by a single sting. Such persons usually carry a sting kit to give themselves a shot in the event of a sting. Pest professionals with such an allergy should avoid conducting treatments for social bees and wasps and need to be extra alert for the presence of stinging pests. They also need to keep their sting kit close at hand. In at least one case, a service professional who left his sting kit in his truck collapsed and died in a backyard because he couldn’t reach his truck in time after being stung once while performing routine pest control service at a home.

KNOW YOUR FOE. Stinging pests take a number of forms and most are not particularly aggressive. For example, carpenter bees and cicada killers frighten many people as the males may fly at them in an attempt to protect the nest the females are constructing and provisioning. Yet, males have no stingers and the females keep themselves very busy at their tasks. Conversely, firing up a leaf blower or lawnmower near a nest of social bees or wasps can provoke an attack. (I once "discovered" three separate nests of yellowjackets in my yard during a one-month period just by using my lawnmower.)

Knowing the stinging pests in your area and being alert while working outside can keep one relatively safe. (For example, don’t follow my example by trying to drill and treat a foundation for termites directly below a honey bee nest in the wall. A single sting to the forehead discouraged me from ever attempting that foolish stunt again without first treating the bee nest or wearing a bee suit. Pain can be an excellent teacher.)

When considering the stinging pests in your area, know which are solitary creatures and which live in social colonies. Fire ants and certain bees (honey bees, bumble bees) and wasps (paper wasps, yellowjackets and hornets) are social insects. Common solitary stingers include scorpions, carpenter bees, mud daubers and cicada killers. Less common are the numerous solitary bees and wasps such as velvet ants, leaf cutter bees, and "digger" bees and wasps. Social insects by far pose a larger risk: greater numbers plus aggressiveness equals increased chances for stings.

It is fairly obvious that social insects are involved in a particular situation by the numbers of active bees or wasps seen around the nest. It is less obvious, however, if a single bee or wasp is found dead inside by a customer. It is in these instances that one needs to be able to identify between the various types of bees or wasps.

Another important consideration is the fact that honey bee colonies are perennial in nature. A customer reporting that the bees have been in place a few years may mean more areas will need to be addressed inside the building to reach the entire colony. Colonies of bumble bees, hornets, paper wasps and yellowjackets live only one year with the exception of certain yellowjacket species in Florida that can survive perennially.

Honey bees also abscond (or swarm) each year in an attempt to form new colonies. Such swarms sometimes take refuge near or on a building, provoking fear on the part of the building’s occupants. Typically, the swarm moves on in a day or two unless they discover a void within the structure suitable to nest within. Convincing a customer to let the swarm be until it moves on is difficult, and they usually request it be taken care of. A professional beekeeper may often come and retrieve the bees for use in his operation. If not, the swarm may need to be removed by using one of the techniques discussed below.

One additional honey bee note: Africanized honey bees are well established in the southwest U.S. from Texas to Southern California. They have recently been confirmed in Arkansas and Florida. This species is particularly aggressive, and colonies have been known to "go off," meaning the bees fan out and sting any living thing within a city block area or further. Angry worker bees have been known to chase people for a quarter of a mile or further. Fortunately, it appears in the United States that Africanized bees are losing some of their aggressiveness and are not nearly the "killers" they have been in South and Central America. However, one cannot identify between Africanized and European honey bees by looking at them — the honey bees must be examined by an expert to be positive of the bee’s true identity.

PROTECT THYSELF. In my younger, more foolish days, I treated social bee and wasp nests without wearing protective gear. I never was stung any of those times, but it wasn’t the smartest thing to do. Interestingly, the only time I have been stung while treating bee or wasps nests was while wearing the bee suit, veil and a pair of heavy gloves. I was also working at night because the bumble bee nest was tucked deep within a large mound of pampas grass. My mistake was wearing ordinary heavy garden gloves. A single bee found the base of my hand where a tiny sliver of skin remained exposed as I stretched into the grass to treat the nest. Lesson learned — I now own and use authentic beekeeping gloves that reach above my elbows.

And for you professionals who may be "calorically challenged," be sure the netting on your bee veil doesn’t touch your neck. A portly colleague of mine standing on a ladder while treating a bald-faced hornet nest was stung when the "extra" part of his chin brushed against the screen of the veil. Needless to say, he was quite shocked and reacted by falling off the ladder. Fortunately, he was not injured beyond the pain of the sting.

DEGREE OF DIFFICULTY. Bee and wasp work should be priced according to its degree of difficulty. Those nests at ground level are far easier to treat than those where one needs a 24-foot extension ladder. Treating a yellowjacket nest in an exposed landscape bed is simpler than treating a nest housed within the wall and floor of a home. Honeybee nests may be more difficult because (1) they may have been in place longer, thus covering a larger number of voids within the walls, and (2) the honey and combs can be restrictive to good distribution of any insecticide applied. Professionals should plan ahead for all of the factors that might be involved in successfully eliminating a social bee or wasp nest.

BASIC PRACTICES. The treatment of social bee and wasp nests usually is not that involved, especially those that occur outside and not within a building. The key will be ensuring adequate dispersal of insecticide throughout the nest, leaving plenty of residual behind to kill newly emerging adult insects as they leave their protective pupal cases.

It must be stressed again that persons even moderately allergic to insect stings refrain from intentionally performing social bee and wasp work. Also, when conducting such work outside, suitable bee protection gear should be worn. Lastly, although such treatments can be performed during the day, applications made at night enjoy a bit larger safety factor and most of the bees and wasps will be in the nest. It might be preferable that anytime one must treat a nest more than 10-12 feet above the ground or when treating honey bees in areas where Africanized bees might be present that the services be conducted after dusk.

Ground nests. Ground nests of yellowjackets and bumble bees are typically easily treated as the voids within the ground are generally smaller and contained nicely within the soil. Once the entrance hole is known, injection of a few seconds of pyrethrins-based aerosol followed by application of a residual dust does the trick. It is helpful, I’ve found, to use extension tubes on the tip of the duster and extend the application down into the hole. (In experimenting once with one of my own yard-based yellowjacket nests, I placed a small pile of dust into the nest entrance and forced it in using my leaf blower. I got excellent penetration and coverage within the nest.)

In sensitive situations, such as the play area at a school or day care, a ground nest can be "treated" by visiting at night and using a Shop-Vac® to remove most of the wasps. A pyrethrins aerosol is then applied into the nest to subdue any stragglers and then a shovel used to dig up the nest. Fresh soil is used to fill the hole after removing the nest.

Aerial nests. Bald-faced hornets and European hornets construct large paper nests within the branches of trees and shrubs and are known to build nests on the outside of buildings. European hornets, however, have also been found living within chimneys and other large voids (e.g., hollow trees).

Aerial hornet nests within reach of the ground are relatively simple to treat although one hidden deep within the thick branches of a shrub can pose some difficulty. Nests requiring a ladder to reach are problematic depending on their location and how high they are above the ground.

I am not a fan of using a high pressure hose spray to "blast" a nest from its perch. Either one should acquire the right ladder or lift for the job or devise another way to reach the nest. Fortunately, in my experience, most all of the hornet nests that cause problems for homeowners aren’t the ones that are 15 or more feet above ground. It is usually the ones within 10 or so feet that are bothersome.

The paper envelope of a hornet nest makes an excellent chamber to contain an insecticide application. I prefer not to apply the treatment through the nest entry hole. It is a bit safer to approach from the rear and poke the tip through the back of the nest. I’ve found that application of a few seconds of a pyrethrins aerosol followed by residual dust works well. The dusts available today don’t have the knockdown enjoyed by Ficam so the pyrethrins disrupt, knock down and confuse the wasps long enough to apply an appropriate amount of residual dust. After 15 minutes or so the nest can be cut out of the tree or shrub and removed to a sealed plastic trash bag.

I believe that most pest management professionals likely treat hornet nests during the day. Daytime treatment and nest removal occasionally results in a return service visit. On a few occasions, hornets out foraging when the treatment is being completed have returned to find their nest gone. These hornets then begin constructing a new nest in its place, thus prompting the customer to call again for service. This factor needs to be kept in mind when dealing with hornet nests.

Nests within voids. When yellowjackets or honey bees nest within the voids of a building, the first step a professional should take is to determine exactly which voids are involved. This task can be accomplished using a stethoscope to listen into walls, floors and ceilings. Tapping on walls stimulates activity making the colony easier to detect. More often than not, the voids infested are not directly behind where the bees or wasps are entering from outside.

The more effective method for treating void nests is to drill directly into the voids where the insects are located and apply residual insecticides. Keep in mind that these walls are often insulated and hand-operated dusters may not force insecticide through the insulation for adequate dispersal. Drilling several holes over the extent of the nest increases penetration and distribution of the treatment. Use an electric duster or even an aerosol generating machine (e.g., Micro-Injector™).

In most cases, customers will permit drilling from the inside, but on occasion, expensive wall coverings preclude inside drilling. Furthermore, the outside may be covered by brick or siding that the customer prefers not be drilled. In such cases, the only option may be to treat through the entry hole on the exterior. This option can prove difficult especially when the nest is located within a void many feet from the entry hole. The use of an electric duster or an aerosol generating machine may provide the penetration through to and into the colony in the void. For this situation it is advised the treatment be conducted at night when most all of the bees or wasps are in the nest.

When honey bees are involved the customer should be advised they will need to open the void and remove the comb and honey, otherwise odors, seepage and other pests will arise. The honey within has been treated and is therefore not edible.

Honey bee swarms. Honey bees are valuable and beneficial insects and need to be preserved wherever possible. Try first to convince the customer that the swarm most likely will leave on its own within a day or two. If unconvinced, a call to a beekeeper may result in the beekeeper removing the swarm.

Should a customer insist that a bee swarm be removed or if it is in a place where children frequent, such as a school or day care, it may need to be treated or otherwise removed. Working at night, a honey bee swarm can be removed using a Shop-Vac. Or, treat the swarm with a spray of very soapy water or with a residual insecticide or a wasp aerosol product. You should be familiar with your state’s regulations (e.g., California), however, regarding conservation of honey bees before removing or killing any honey bee swarm.

SUMMARY. Bee and wasp work can be profitable, especially during the mid to late summer when colonies of these insects grow large and become more noticeable. To engage in this work, professionals need to be prepared with the right equipment and also be prepared to work at night or the early morning hours when the situation calls for it. It also pays to prepare your technicians now for such work later. Social bees and wasps pose the greatest immediate health risk of any pest professionals might encounter and quick response and careful applications of control guidelines will be greatly appreciated by customers.

The author is manager of technical services, Terminix International, Memphis, Tenn. He can be reached at shedges@giemedia.com.