55 



have required an amount of time which was not in my power to bestow upon its prepar- 

 tion. In Bulletin No. 7 of the U. S. Entomological Division, prepared by Dr. Packard, 

 in 1881, upon the Insects Injurious to forest and shade trees, there are enumerated 

 one hundred species infesting the willows. Those recorded in my own notes, and the 

 records made by other entomologists which I have been able to examine while writing 

 this paper increase the number to at least two hundred. Even this large list would 

 probably be almost doubled, if careful observations were made in all parts of the 

 country, for in Europe four hundred species are known to feed upon the various willows. 



INSECTS INJURIOUS TO THE OAK. 



BY F. B. CAULPIELD, MONTREAL, P. Q. 



If we examine a tree during the summer months it will generally be found abund- 

 antly tenanted by insects, some resting upon the trunk and larger limbs, while numbers 

 may be observed upon the leaves, either sleeping or busily engaged devouring them, or 

 else converting them into dwellings to afford them shelter from the storms and rains, or 

 to conceal them from the numerous enemies who are constantly seeking for them. Every 

 portion of the tree has its insect guests, each quietly and effectually performing its 

 alloted task. It seems to be a law of nature that the old and weak must give place to 

 the young and vigorous, hence a tree that has been unable to withstand the storm, or 

 has been injured in any way, is speedily attacked by insects, conspicuous amongst them 

 being the long-horned beetles, Cerambycidae ; these bore into and tunnel it in all direc- 

 tions, permitting the air and moisture to enter, thus hastening its decay, and soon the 

 massive trunk moulders and crumbles into dust, allowing a fresh growth to spring up 

 -and fill its place. In this way, so long as the forest is left in its natural condition the 

 insects perform a good work. But when man steps in and the forest gives place to the 

 orchard and the trees are reserved or planted for shade or ornament, the case is different, 

 and it behoves us to study the habits of the insect inhabitants so that we may not con- 

 found the good with the evil, that we may know the times of their appearance and the 

 particular manner in which the different species work, in order that we may be prepared 

 to take effective measures to exterminate such as are injurious, and protect and foster 

 those which are beneficial. 



I have, in this article, endeavored to give a brief account of some insects known to 

 injure oak trees, (Quercus) drawing freely upon those entomologists who have contributed 

 so largely to our knowledge of the subject. 



Injuring the Trunk. 



1, The Locust Carpenter Moth. Xyleutes robinice (Harris.) Order Lepidov- 

 tera, Family, Bombycidae. 



This is probably the most injurious insect attacking the red oak, and is equally de- 

 structive to the locust and several species of poplar. The female measures about three 

 inches across the expanded wings, the front wings are grey marked with a network of 

 dusky lines and spots, the hind wings are dusky, and darker at the base. The male is 

 much smaller, and his front wings are darker than those of the female, the hind wings 

 are black, with a large ochre-yellow spot. Dr. Harris states that the moths come forth 

 about the middle of July. Dr. Fitch gives June and the forepart of July as the time of 

 their appearance, the latter agrees with my own experience. During the day the moths 

 remain quiet upon the trees, indeed I doubt that the female ever flies to any great dis- 

 tance, as her body is so large and unwieldy, owing to the number of eggs with which it 



