Carolina paper wasps are large wasps with burnt-orange colored bodies and black wings. Actually there are two species that look very similar, Polistes carolina and P. rubiginosus (formarly P. perplexus). These wasps build paper nests similar to other paper wasps, but prefer to build in protected areas where the nest is hidden from view. While other species of paper wasps may build their nests underneath the eaves/soffit of buildings, Carolinia paper wasps prefer to build inside the eaves, or inside similar building voids.
Of course, they can only do this if they can gain access to the void through some type of crack or opening. The nest may be located well back in the void, several feet away from the opening. Because their nests are usually in such protected locations, one might think these wasps would be less defensive than other species, but this is definitely not the case.
Several guards are usually stationed around the access opening and they are quick to attack anything they perceive to be a threat. As a result, this is one of the most problematic wasps around older buildings or buildings that have cracks or openings to suitable nest sites. They will often attack and sting people who are mowing, working or playing around the area, or just walking by.
The fact that the nest is located inside a void where it is protected, and usually not visible, makes Carolinia paper wasps more difficult to control than other paper wasps. You can’t just walk up with a can of wasp spray, spray the nest and be done.
One option is to hire a professional pest control company to deal with the problem. For people who are especially sensitive/hypersensitive to wasp stings, this is the only wise option. If you choose to do-it-yourself, first recognize that there is always a risk of getting stung when dealing with stinging insects.
Second, realize that your chances of getting stung are much less if you wear protective clothing/equipment. Also, it is helpful to know that wasps are less likely to fly after dark, though they will fly to a light when disturbed. And, be sure to take appropriate care when working from a ladder and/or around sources of electricity. Risks of falls and other mistakes are magnified when you have stinging insects flying around your face!
Following are some of the better treatment options and general ideas on how to use them, but, every situation is different and you will have to use your own judgement to decide which tools to use and how to best use them.
One of the most effective treatments requires the use of two different aerosol spray products.
First, use a can of fast-killing wasp and hornet spray, the kind that shoots several feet, to kill the guards at the entrance, and to do this for several days in a row to deplete the population of adult wasps. Then use a can of Bengal Roach Spray II — the formulation that is 2 percent permethrin and comes with the little spray injection straw, and inject this spray into the void where the nest is located.
This product is not as fast-killing as the aerosol wasp and hornet sprays, but it provides an effective method of injecting a long-lasting insecticide mist into the void where the nest is located. This comes in an aerosol spray can with a straw that can be used to inject the spray into the void. The aerosol mist from the Bengal Roach Spray product will usually move far enough in the void to reach the nest and kill any remaining adults and brood.
Wearing protective clothing and/or treating after dark is the best way to reduce the chance of stings while applying this spray. Some companies sell extension poles that can be used to apply aerosol sprays. These are useful tools, but be especially aware of electrical hazards when using extension poles.
Another treatment option is to inject an insecticide dust (0.05 percent deltamethrin: Delta Dust or Terro Ant Dust, or Enforcer Ant Dust are brand name products) into the void — through the entrance hole, and allow time for the dust to work. This can take several days and you may need to reapply the dust.
The idea is to apply the dust where the wasps have to track through it to get to and from the nest. Several company sell tools such as bulb dusters and extension poles that can be used to apply the dust (usually have to order these from on-line sources). Wearing protective clothing and treating at night will reduce the chances for stings. It is a good idea to use a can of wasp and hornet spray to kill the guards around the entrance — and continue treating wasps as they appear (either coming out from the nest or returning to the nest) until you have depleted the population, and then apply the dust.
Once you have eliminated all nests around a building it is important to promptly seal/repair the cracks/openings where the wasps got into the void. Otherwise, they will come back.
For more information on gardening, contact Leanna McGee, Extension Agent II at 601-635-7011.
