Wasps have intrigued people for several centuries. Their color, their activity, and their painful sting have made them the sources of interest or worry to many people. Of many wasp species found in North America, only a few wasps are of a direct concern to the homeowner. Your best bet to achieve control over wasps is to find the nest and destroy the colony by applying insecticides, which you will read in detail in this article below.
Wasps and bees can be a serious nuisance, particularly late in the summer when certain yellowjacket wasps forage at garbage and outdoor food areas. In overall balance, however, these insects are beneficial in their activities, particularly as predators of pest insects and as pollinators. It is important to distinguish between the various wasps and bees because their potential as problems and their control differ.
Interesting Facts about Wasps
Several wasps are social insects that produce a colony. Colonies begin a new each spring, initiated by a single fertilized female (queen) that has survived winter. The social wasps construct their nest of paper, which they produce by chewing on wood, scraps of paper and cardboard. Social wasp colonies are very small early in the season but expand rapidly through the summer as more wasps are raised that assist in colony development.
By the end of summer, a colony may include dozens, or even several hundred individuals. Some wasps reared at the end of the season are fertile females (potential queens) and a few males. In fall, colonies are abandoned, never to be reused, and the fertilized females scatter to find protection during winter. The remaining members of the colony perish with cold weather.
Most social wasps rear their young on a diet of live insects. Several types of social wasps are important in controlling insect pests such as caterpillars. An exception to this is the western yellowjacket which primarily scavenges dead insects, earthworms and other carrion, including garbage. This scavenging habit is usually why yellowjackets become serious nuisance problems.
Male wasps occasionally visit flowers to feed on nectar, however, social wasps are generally not important plant pollinators. All social wasps are capable of producing a painful sting but none leave the stinger embedded, as do honey bee workers. Most stings occur when the colony is accidentally disturbed.
Types of social wasps
Yellowjackets
Yellowjackets (Vespula spp.) are banded yellow or orange and black and are commonly mistaken for honey bees, but they lack the hairy body and are more intensely colored. Yellowjackets typically nest underground using existing hollows. Occasionally nests can be found in dark, enclosed areas of a building, such as crawl spaces or wall voids. Nests are enclosed in a paper envelope, but they are not exposed nor observed unless excavated. The nest entrance is small and inconspicuous. Colonies are readily defended and yellowjackets will sting when the nest area if disturbed.
The western yellowjacket (V. pensylvanica) is, by far, the most important stinging insect in North America. Late in the season, when colonies may include up to 200 individuals, they become serious nuisance pests around outdoor sources of food or garbage. The western yellowjacket is estimated to cause at least 90 percent of the “bee stings”.
Baldfaced Hornets
Hornets (Dolichovespula spp.) produce large, conspicuous grayish paper nests in trees, shrubs and under building eaves. The most common species is the baldfaced hornet (D. maculata) which is stout-bodied and marked with dark and white striping. Hornets feed their young live insects and do not share the scavenging habit of yellowjackets. Nests often attract attention because of their large size, but hornets rarely sting unless the colony is seriously disturbed.
Paper wasps
Paper wasps (Polistes spp. and the western paper wasp, Mischocyttarus flavitarsus) make paper, open cell nests which are not covered by a papery envelope. Often these nests are produced under building overhangs.
However, a new species to North America, the European paper wasp (Polistes dominulus), will also nest in small cavities in the sides of buildings, within metal gutters and poles, outdoor grills, and similar items. Paper wasps are more slender-bodied than other social wasps. Most native paper wasps are reddish-brown and marked with yellow, but the European paper wasp is marked with shiny black and yellow, allowing it to be easily mistaken for a yellowjacket.
Paper wasps are beneficial predators of caterpillars and other insects and do not scavenge. However, the habit of the European paper wasp to nest in many locations around a yard has greatly increased the incidence of stings associated with this group of wasps.
10 Tips on DIY Wasp Control
1. Your best bet to achieve control over wasps is to find the nest and destroy the colony.
2. Apply insecticides You may choose from the several insecticides that are effective. One percent dichlorvos (DDVP), 2% malathion, or 1% ronnel may be used. The last two are slower acting and if the material also contains pyrethrins, there will be a faster knockdown of the wasps and less chance of being stung.
3. Generally, insecticidal dusts are best for terrestrial (underground) nests and insecticidal sprays for aerial nests. Throw a shovelful of dirt over the entrance hole of an underground nest after the insecticide is applied.
4. Make sure that control measures are undertaken only at night when the wasps are less active and when all are present on or in the nest. You might as well take advantage of cold or wet weather, which will also reduce the possibility of stings.
5. If you want to be further cautious, wear high shoes, gloves, a hat, and heavy clothes that can be tied about the wrists and ankles. A face veil will give extra protection. If you are using a flashlight, hold it to one side at arms length so if the wasps fly toward the light, they will be drawn away from the body.
6. Never risk being stung by a wasp in attempt to spray their nest, if you are allergic to wasp venom.
7. If you choose not to use regular insecticide, you can pour gasoline down the entrance hole of an underground colony. The fumes kill the adults, but not the pupae, so some adults will appear afterward if the nest is not dug up and destroyed.
8. To destroy aerial nests, you can burn them by attaching a torch to a pole and holding the fire to the bottom of the nest. You must proceed with great caution if the nest happened to be on an evergreen tree or a house.
9. Sometimes no matter how hard you try, it is just impossible to trace an underground nest, then toxic bait stations may come in handy to reduce some of the hostile population. But keep in mind, that you must present the bait to yellowjackets in a safe way so that you don’t pose danger to other animals. Here we want to describe the following safe method.
You need make a five-inch square box from ½ inch mesh wire screening; one side has to be hinged so that bait can be put in, and you will have to suspend it from a branch by a wire. You want to make the box and hang it so that other animals cannot enter or destroy it. The suspended wire must be coated with Tanglefoot or Stikem to keep out crawling insects.
10. To prepare the bate use fish-flavored cat food or canned tuna fish mixed with chlordane wettable powder to make a 1% mixture and place it in a shallow pan on the bottom of the cage. So, this is how it works – adult yellowjackets pass through the screening, pick up the meat and carry it back to feed their young, so gradually poisoning the whole colony.
In general, no control is required for the solitary, ground-nesting wasps and bees, but if the necessity does arise, the same insecticides as listed for yellowjackets may be used.