1910 ENTOMOLOGICAL SOCIETY. 13 



Attacking Forest and Shade Trees. 



Cankerworm larvae were more abundant in the spring of 1909 than they were 

 in 1908. On the 4th June they were half grown. At Beechwood, just outside of 

 Ottawa, beech trees were badly attacked, the result of their depredations being 

 easily seen. When ornamental trees are attacked by these caterpillars, it is import- 

 ant to apply the arsenical poison while they are small. They can then be easily 

 killed at the ordinary strength used for leaf-eating insects. When they are more 

 than half an inch long they are a good deal more difficult to kill, and consequently 

 much stronger sprays must be used. 



The Spiny Elm Caterpillar (Euvanessa antiopa, L.) was abundant on elm trees 

 throughout the district. On June 21, larvae about one and a quarter inches long 

 were noticed. Specimens which were collected had become full grown and changed 

 to chrysalids by July 10. The species is intermittently abundant at Ottawa, and 

 some years it is not an uncommon sight to see small elm and willow trees entirely 

 stripped of their foliage. 



Elm trees seemed to be particularly attacked by insects during the past sea- 

 son. The Woolly Elm-leaf Aphid was very aibundant and many enquiries were 

 received concerning it. By the middle of June the conspicuous colonies were much 

 noticed. The Cockscomb Gall was also, numerous in the district, the leaves of many 

 elm trees being covered with these galls. Near Maniwaki, Que., on July 29, I saw 

 large numbers of the Plum Gall, Pemphigus ulmi*fuscus. The galls were large 

 and on most of the leaves of the infested trees there were at least two and very 

 often three or four galls present. 



The Spruce Budworm (Tortrix fumiferana, Clemens.) This insect caused 

 much anxiety among the lumbermen of the Ottawa district. Reports were received 

 from the upper Gatineau that some insect was ravaging the spruce and balsam 

 forests, and as a result I was sent up into the infested area to find out tlie nature 

 of the trouble. The result of this investigation is given in a separate paper which 

 I hope to present shortly. At Ottawa, thousands of the moths were noticed flying 

 around bushes and trees of all kinds on July 20th. They were even abundant all 

 through the city, and on almost any bush or tree being disturbed, many of the 

 moths would fly out from the foliage on which they were resting. 



The Larch Sawfly (Nematiis Erichsonii, Hartgn.) was also very prevalent 

 wherever larches were growing. It was noticed in considerable numbers on some 

 ornamental larches on the Experimental Farm, on July 20, and at this time the 

 larva? were about full grown. Up the Gatineau River from Ottawa as far north 

 as Baskatong, I noticed all through this area at the end of July the results of the 

 work of this larvae. Many trees were entirely stripped of their foliage. Along the 

 railway, between Ottawa and Montreal, the defoliation of these handsome trees 

 was also conspicuous. 



The work of the Spruce Sawfly was also noticed to some extent north of 

 Maniwaki, and larvae were found to be full grown on July 30. At this date most 

 of the larvge had disappeared. 



The Bronze Birch Borer {Agrilus anxkis, Gory.) is serio,usly injuring birches 

 in the Ottawa district. The result of the work of this insect is easily seen at the 

 Central Experimental Farm, where practically all of the cut-leaved birches are 

 dying. This insect has not been mentioned very much in Canada as yet, but in 

 northern portions of the United States it has done a good deal of damage. The 

 presence of this borer is soon shown by the dying of the tops of the trees. This 



