IPMP3.0, Oregon State University, Copyright 2000




Fact Sheet (requires Acrobat Reader 3.x or above to read and print. Click below to download the free "Reader".)

Download Acrobat Reader Software

Registered Insecticides


[Insect Management]


Link to large image (103K) of Hymenoptera Parasite Adult

In most instances, development of parasite populations lags behind that of the prey, which may result in large numbers of pests being present before sufficient numbers of parasites are present to control pest populations. Nevertheless, parasites are important regulating factors of pests in mint. Parasitized insects are frequently conspicuous enough to be observed in the field - usually swollen or immobile. If the parasite has matured, the host may be covered with tiny cocoons or it may be hollow.  Parasites of aphids form cocoons either in or under the swollen, tan, mummified skeleton of the aphid. It is important to look for parasitized insects when fields are being routinely sampled for the presence of pest insects. If a large number of parasitized insects are found, it may not be necessary to treat with an insecticide.

Link to large image (105K) of Hymenoptera Parasite Adult

Link to large image (119K) of Hymenoptera Parasite Adult

Hymenoptera Parasite Adult Hymenoptera Parasite Adults
Link to large image (119K) of Hymenoptera Parasite Larvae Most parasites (also called parasitoids) are tiny wasps, which are easily overlooked. Adult parasites range in size from very small (0.3 to 3 mm long) to 20 to 35 mm long.  Most range in size from 2 to 15 mm. Larvae of most Hymenoptera parasites develop inside the bodies of their prey, but some feed externally or pupate outside the host's body. Most Hymenoptera parasites overwinter as pupae or prepupae in the soil, under trash, within prey, or in other protected areas. Adult emergence in the spring is closely synchronized with the prey. Females lay an egg in or on the prey and the parasite larva consumes internal tissues and organs, eventually killing the prey. Many parasites have numerous overlapping generations during the summer, but some species have only one generation each year. These parasites are important in suppressing populations of many insects. In mint, they are important for control of loopers, cutworms, and aphids (see Coop and Berry, 1986).

Hymenoptera Parasite Larvae on Prey

View the Fact Sheet for More Information

This section contains information on the identification of Hymenoptera parasites.  The Fact Sheet contains specific information on identifcation and biology of these parasites (requires Acrobat Reader).