Bug of the Month July 2016: Grapevine Beetle

Subject: Idk what it is
Location: Womelsdorf pa
June 29, 2016 2:57 pm
This beatles looking about the size of a dime if not a bit bigger has been on our outside light for a few days.
Signature: Connie Wansley

Grapevine Beetle
Grapevine Beetle

Dear Connie,
Also known as a Spotted June Beetle, this Grapevine Beetle,
Pelidnota punctata, is closer to the size of a quarter than a dime.  They are about an inch long.  Since it is the end of the month, we need to select a Bug of the Month for July 2016, and we have decided to feature your submission.  According to BugGuide:  “Adults feed on grape (Vitis) foliage and fruit Larvae host on dead Acer, Celtis, Juglans, Malus, Platanus, Quercus, Ulmus spp [a variety of hardwood trees]” and “Eggs are laid on stumps and rotting logs. Larvae feed on decaying roots and stumps of trees, pupate in adjacent soil. Adults emerge May-September and come to lights.”  According to the University of Wisconsin at Madison:  “Look for GBs east of the Great Plains, in woodlands, thickets, vineyards and gardens – places where rotting wood/stumps are found near grape vines. Adults eat the leaves of grape (wild and domestic) and Virginia creeper (and there’s one account of a GB browsing on spinach in a garden), and the larvae (grubs) feed on rotting wood. Most sources say that the adults do minimal damage in a well-kept vineyard and do not need ‘controlling’.  Ms. GB lays her eggs in stumps and other rotting wood, or on the ground near stumps and rotting wood, apparently favoring dead elm, oak, maple, apple, and hickory. The pale, C-shaped larvae hatch two weeks later, dig/bore in, and feed – and feed, and feed – for the rest of their first year and through their second summer. They eventually reach two inches in length and pupate underground, not surfacing until they emerge as adults the following year.” 

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