124 



THE REPORT OF THE 



No. 19 



as they had gone into, and were working in, the centre of the root. Damage 

 was also done to the roots of some seedlings by the Lachnosterna larvae. 

 (See Fig. 6.) I regret that I am unable to identify the above species. 

 However, I expect they will give me sufficient opportunity to further study 

 them. The foliage of forest trees suffers from the work of a great variety 

 of insects. This injury is not only unsightly but from the forester's stand- 

 point hinders the proper development of the stem of the tree. Defoliation 

 cuts off the food supply and so lessens the amount of wood laid on during 

 the season. Considerable damage is annually being done by Lepidopterous 

 larvae. Owing to the fact that their life history is more easily followed 

 than that of other orders there is considerable known and written concern- 

 ing their work. 



Fig. 60. Larch Saw fly ; a, with outspread wings ; h, the brown pupa case — both greatly n 

 enlarged ; c, terminal twig of Larch showing eggs in slits made by the female saw-fly. 



The Larch Saw-fly, (Fig. 60), a hymenopterous leaf destroyer, has done 

 an enormous amount of damage in Canada. The tamarac has suffered from 

 this insect throughout its known area of distribution and as yet its natural 

 enemies have not controlled it. In the vicinity of Guelph this insect has 

 done considerable damage to the European larch and our native tamarac 

 during the last season. 



Coleoptera, in both the larval and adult form, are responsible for dam- 

 age done to the foliage. The Lamellicorns and Chrysomelids both feed upon 

 the leaf iji the adult form. Lachnosterna frequently does damage to the 

 maple and other leaves, but not to any serious extent. The basswood or 

 linden leaf seems to suffer most from their attacks and late in the summer 

 it is almost impossible to find a perfect leaf. Large numbers of Macrodac- 

 tylus suhspinosus (Fig. 30) and Odontota rubra have been taken from this 

 tree in beating operations and probably they are responsible for a great 

 share of the damage done. Of the Coleoptera the Chrysomelids in the larval 

 and adult stages do most damage to the leaves of forest trees. 



Roots are attacked by the larvae of Prionids and Lamellicorns. Buds 

 have enemies in the Curculionidae and Lepidoptera. Deformities on ter- 

 minal branches are formed by Aphidse, Cynipidae and Cerambycidae. 



