1880. 



AND HORTICULTURIST. 



61 



Forestry. 



COMMUNICA TIONS. 



PINE-TREE INSECTS. 



BY WM. SAUNDERS, LONDON, ONTARIO. 



The following, from the annual address of the 

 President of the Entomological Society of On- 

 tario, is from the Canadian Entomologist : The 

 City of Ottawa being one of the great centres of 

 •our lumbering interest, it seems fitting that I 

 should on this occasion call your particular at- 

 tention to some of those insects most injurious 

 to our pine forests. The losses occasioned by 

 the destructive work of borers in pine trees 

 "both before and after the}'^ are cut are unfortu- 

 nately too well known to those interested in the 

 lumber trade, although the sufferers may not be 

 familiar with the life histories of their enemies 

 ■so as to be able to recognize them in the various 

 stages of their existence. The lumberman suf- 

 fers from the work of a number of destructive 

 species, nearly all of which inflict their greatest 

 injuries during the larval stage of their ex- 

 istence. 



There are three families of beetles in which 

 ■are included the greater number of our enemies 

 in this department. I allude to the longicorns 

 or long-horned beetles, Cerambycidse ; the serri- 

 corn or saw-horn beetles, Buprestidas, and the 

 cylindrical bark beetles, Scolytidse. To go over 

 this long series in detail would weary you. A 

 brief sketch of the life history of a single ex- 

 ample in each family will serve as representa- 

 tives of the whole. 



One of the most destructive of the species in- 

 •cluded in the Cerambycidse is a large grey beetle 

 with very long horns, known to entomolog- 

 ists under the name of Monohammus confusor, 

 and popularly in this district as the " Ottawa 

 Cow." Where trees have become diseased from 

 any cause, or wliere a fire has ravaged a pine 

 forest, and scorched and partially destroyed 

 the timber, or where logs after being cut have 

 been allowed to remain a season in the woods 

 •or in the mill yard — there these insects gather 

 and soon multiply to a prodigious extent. The 

 mature insect is over an inch in length; the an- 

 tenniie of the male reaches the extraordinary 

 length of from two to three inches, while_those 



of the female are shorter. The female lays her 

 eggs in the crevices of the bark, where the lar- 

 vse when hatched eat their way into the wood, 

 burrowing extensive galleries through the solid 

 timber; when mature they are large, white, al- 

 most cylindrical, footless grubs. They pass their 

 chrysalis stage within their burrows, and the 

 perfect insect on its escape eats its way out 

 through the bark. There are about a dozen 

 species in this family known to be destructive 

 to pine. 



; Most of the insects belonging to the family 

 Buprestidee may be recognized by their brilliant 

 metallic colors ; they have very short antennae 

 which are notched on one side like the teeth of 

 a saw, and are often hidden from view by being 

 borne under the thorax. Chalcophora liberta is 

 one of the most destructive to pine trees, and 

 its liistory is very similar to that of the long- 

 horned beetle just described, but the larva is of 

 a different form, and has the anterior segments 

 or rings of the body very large, reminding one 

 of the appearance of a tadpole. The perfect 

 insect is about three-quarters of an inch long, of 

 a brassy or coppery hue, with the thorax and 

 wing-covers deeply furrowed by irregular lon- 

 gitudinal depressions. Dr. Fitch enumerates 

 twelve species belonging to this family which 

 are known to be injurious to pine. Additional 

 information in reference to these beetles may 

 be found in an article contained in the last an- 

 I nual report of our Society, by Mr. J. Fletcher, 

 \ of Ottawa. 



The cylindi'ical bark beetles, Scolytidte, are 

 I also a numerous family, eight species of which 

 are known to attack pine. The boring Hylur- 

 gus, Hylurgus terebrans, is probably one of the 

 commonest. This beetle is about a quarter of 

 an inch long, of a chestnut red color, thinly 

 clothed with yellowish hairs, and is found during 

 the month of May. The larva, which is a small 

 5^ellowish white footless grub, bores winding 

 passages in every direction in the inner layers 

 of the bark of the tree, and also through the 

 outer surface of the wood. 



In some parts of our Province pines are 

 greatly injured and sometimes killed by the 

 attacks of a woolly bark louse, which covers 



