HORNETS, WASPS AND YELLOW JACKETS
WASP NEST REMOVAL
Adult worker wasps have the characteristic black and yellow patterning on the abdomen and are between 15 - 20 mm long. They have a black head and thorax.
The fore and hind wings are held together by a row of minute hooks giving the appearance of only one wing per side of the wasp. The wings are heavily veined.
The wasps are colonial insects living in social groups. Each colony is established in the spring by an overwintering queen which makes a smaller starter nest from paper made by itself by mixing wood and saliva.
The colony grows throughout the summer and the nest with it. Many thousand individuals are often to be found associated with each nest, with the workers feeding on nectar, sweet materials and at certain times insect larvae and other animal pieces.
The colony develops males towards the end of the summer to mate with the presumptive queens which when mated overwinter start a new colony the following year.
Worldwide. Dolichovespula norvegica, the Norwegian wasp, and Dolichovespula sylvestris, the tree wasp, are two native British species. In recent years, Dolichovespula saxonica, and Dolichovespula media have been recorded in the UK.
Dolichovespula spp usually produce grey aerial nests, which have a regular laminar construction. They may be suspended from trees, nest boxes, bee hives, rafters and dormer windows. If nests are formed underground, the envelope is always visible.
The wasps can cause alarm when present in large numbers and if the nest is in a place where the individuals from it interfere with humans they can inflict painful and sometimes dangerous stings.
The most unusual application of treatment for wasps is an insecticidal dust to the nest, around and into the entrance. Liquid surface sprays can also be used. For control of adult wasps, space sprays can be used indoors or surface sprays can be applied in localised areas.
American and European Yellow Jackets
Yellow JacketYellow-jackets are day-active beneficial, predatory insects. They build a paper-like nest containing several layers of cells. A mature nest may typically have 2,000 - 6,000 cells and 1,000-4,000 workers. They are 3/8" to 5/8" long, depending on the species, with their respective queens being about 25% longer. Most species are black with white markings. Nests are sometimes built in open aerial spots, or within bushes, but most species build their nest in a cavity hollowed out below ground. Some workers act as guards at the entrances to below-ground nests. They are very protective of their nest. Usually only fertilized queens live over the winter. Although yellow jackets are generally not likely to attack and sting humans, they can quickly become very aggressive if their nest is disturbed. After the new fertilized queens have gone into their overwintering sites, the remaining workers begin to seek sweets and garbage near places where humans are active outdoors. They are attracted to sweets or syrups, such as that left in the bottoms of soda cans. These and other sweet things in and around garbage cans or bags can draw dozens or even hundreds of such pest wasps. Since they no longer have a colony to provide for, these yellow jacket workers tend to "hang around" and may even become more aggressive than they were before. They may even try to protect their new food source
Baldfaced Hornets (White Faced Hornets)
Bald Faced HornetBaldfaced hornets are large black wasps 5/8" to ¾" long, with yellow markings and a mostly white face. They are social insects which live in aerial nests. The adults are represented by workers (which are sterile females), queens, and males (which come from unfertilized eggs) and usually appear in the late summer. Only inseminated females winterover in sheltered places.
In the spring the females use chewed-up cellulose to build a paper carton nest of several dozen cells covered by a paper envelope. Each cell contains one egg which was laid as the cell was constructed. After about 30 days, the first 5-7 workers emerge and shortly thereafter take over all the work except for egg laying. The nest will eventually consist of 3-5 rounded paper combs which are attached one below another, and are covered with a many-layered grayish-colored "paper carton". Nest size varies up to 3,500 cells in 5 combs but usually consists of less than 2,000 cells in 3-4 combs and contains 100-400 workers at its peak.
Later in the season, larger reproductive cells are built in which queens and males will be reared, though males are often reared in old worker cells. Newly emerged queens and males leave the nest and mate. Only inseminated queens hibernate and survive the winter. The founding queen, workers, and males all die.
Gray Paper Nest
The large grayish-colored "paper carton" aerial nests are constructed in shrubs at ground level to 66 feet or higher in trees. Nests may also be built on overhangs, utility poles, houses or sheds. At maturity, nests can be quite impressive with sizes of up to 14" in diameter and over 24" in length and usually hang in an exposed location such as from a tree. Adults are extremely protective of the nest and will sting repeatedly if disturbed.