Egg - The white, glistening egg is oval to spherical in shape and 0.33 mm long.
Larva - A wireworm larva has 3 pairs of short legs near its head. M. Communis has a pale yellow to reddish-brown body, a brown, flattened head, and a scalloped last abdominal segment. When fully grown, this wireworm ranges from 21 to 25 mm in length.
Pupa - The white, soft-bodied pupa has no protective covering and is approximately the same size and shape as the adult.
Host Plants - The wireworm, M. Communis, feeds on the roots of many grasses, including corn and many small grain crops. It may also attack the roots, seeds, and tubers of many flower and vegetable crops, especially potatoes and sweet potatoes. This species has been known to infest tobacco.
Damage - This wireworm creates holes in potato and sweet potato roots similar to those caused by the tobacco and southern potato wireworms. However, due to the size of this species, the holes are noticeably larger and deeper than those of other species. Damaged roots and tubers are downgraded and discarded. M. Communis is the most damaging wireworm in the more northern sweet potato-growing areas.
Life History - This wireworm species has a 6-year life cycle. In June of the first year, adults deposit eggs singly among the roots of grasses. First instar larvae emerge in July and begin feeding on roots. Larvae continue to develop throughout the summer and overwinter in the ground as second instars during the first year. Most of these immatures remain in the larval stage for 5 years although life cycles as short as 3 years have been reported. In late July or August of the 6th year, mature larvae construct oval cells 15 to 30 cm deep in the soil and pupate. M. communis adults emerge about 18 days later and feed on pollen before hibernating in protected areas. They become active and deposit eggs the following May or June.
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