786 connecticut experiment station report, 1907-i908. 



Natural Enemies. 



Apparently canker worms are not as highly parasitized as some 

 Other species of injurious insects, and little space is given in 

 literature to natural enemies. Dr. Riley mentions* a mite, 

 Nothrus ovivorus Pack., which Professor A. S. Packard observed 

 feeding upon the eggs ; a four-winged fly of the genus Micro- 

 gaster, which parasitizes the caterpillars ; a species of Platygaster 

 that is a parasite of canker worm eggs ; two large ground beetles, 

 Calosoma scrutator and Calosoma calidum, which devour the cater- 

 pillars, and the potter wasp, Eumenes fraternus, which provisions 

 its cells with the caterpillars. Mr. Robert Brown of Yale Uni- 

 versity has reared a small hymenopterous parasite from the eggs 

 of the fall canker worm in New Haven, but at the time of this 

 writing could not furnish any specimens and the insect remains 

 unidentified. 



In the manuscript of the "Hymenoptera of Connecticut,"" by 

 Mr. Henry L. Viereck, Ichneumon utilis Cress, is stated to be a 

 parasite of canker worms. 



Many birds feed upon canker worms, the most important being 

 the chickadee, bluebird, shrike, robin, creeper, thrush, cuckoo, 

 warblers and woodpeckers. 



Remedies. 

 Early Recommendations. 



As the sex-diflFerences were early known, so were the habits. 

 Remedial treatment was also advocated in the eighteenth century, 

 according to Dr. Samuel Deane, who wrote as follows :f 



"This worm is produced from the eggs of an earth-colored bug, 

 which having continued under ground during winter, passes up 

 on the bodies of apple trees early in the spring. They are hatched 

 as early as the end of May, and are so voracious that in a few 

 weeks they destroy all of the leaves of a tree, prevent its 

 bearing for that year, and the next, and give it the appearance 

 of its having been burnt. As the perspiration of trees is stopped 

 by the loss of their leaves, they sicken and die, in a few years. 



* Second Annual Report on the Noxious, Beneficial and Other Insects 

 of Missouri, 1870, p. 102. 

 t The Newengland Farmer or Georgical Dictionary, 1797. 



