The major insect Infestations during the I960 season were again 

 caused by the spruce budworm, the larch sawfly, the European pine sawfly, 

 and several species of native sawflies on pines. The native forest tent 

 caterpillar, eastern tent caterpillar, and the black-headed budworm showed 

 substantial increases in number, but did not reach serious proportions. 



There was an over-all reduction in the area infested by the spruce 

 budworm. The infestation remained about the same in the Fort Frances Dis- 

 trict, virtually disappeared from the Kenora District, and showed a sharp 

 reduction in intensity in the Sioux Lookout District. In the Port Arthur 

 District there was a slight eastern extension along the southern boundary, 

 but this was accompanied by a reduction in area in the vicinity of Lac 

 des Mille Lacs. In the Geraldton District the over-all area of infesta- 

 tion remained about the same, but there was a considerable reduction in 

 the area classified as heavy. The three isolated infestations in spruce 

 plantations in southern Ontario declined still further in I960. 



Larch sawfly populations across Ontario were variable. In the 

 western areas, populations declined in the Port Arthur District, showed 

 little change in the Kenora District, increased locally in the Sioux Look- 

 out and Geraldton Districts, and increased in the eastern part of the Fort 

 Frances District. Infestation patterns were also irregular throughout 

 northeastern and central Ontario. In southern Ontario severe defoliation 

 occurred on a number of European larch plantations. 



The European pine sawfly again extended its range eastward in 

 the Lake Simcoe District, and now extends over southwestern Ontario as 

 far east as a line approximately from the mouth of the Nottawasaga River 

 to Leaside. 



The forest tent caterpillar caused severe defoliation to hard- 

 woods at widely separated localities in northwestern Ontario and the 



