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cankerworm
cankerworm name for two destructive inchworms , or larvae of geometrid moths. The spring cankerworm ( Paleacrita vernata ) and the fall cankerworm ( Alsophila pometaria ) are named for the seasons at which the adults emerge from underground pupation. The spring cankerworm larva overwinters as a pupa, the fall cankerworm as an egg. The larvae, dark green to brown and about 1 in. (2.5 cm) long, feed on the leaves of orchard and shade trees. The spring cankerworm has two pairs of posterior appendages (prolegs); the fall cankerworm has three. The wingless female lays her eggs on the bark, and one control method is the placing of bands of sticky paper around the tree trunks to trap the females before laying. When alarmed, cankerworms drop and hang suspended in midair at the end of a long silken thread secreted from their mouths; they ascend this thread after the danger has passed. The English sparrow was originally introduced in the United States to combat the spring cankerworm. Cankerworms are classified in the phylum Arthropoda , class Insecta, order Lepidoptera, family Geometridae. For control methods see bulletins of the U.S. Dept. of Agriculture. |
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"cankerworm." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "cankerworm." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1E1-cankerwo.html "cankerworm." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-cankerwo.html |
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cankerworm
can·ker·worm / ˈkangkərˌwərm/ • n. the caterpillar of a North American moth of the family Geometridae (esp. Paleacrita vernata and Alsophila pometaria) that can be a major pest of fruit and shade trees. |
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Cite this article
"cankerworm." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "cankerworm." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O999-cankerworm.html "cankerworm." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-cankerworm.html |
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