Forest Insect and Disease Survey; Ontario, 1965 - NFIS

INTRODUCTION
South-central Forest Region
Changes in the format and in printing methods have resulted in a more compact
report without reducing the amount of data provided. As in recent years tree
disease surveys are dealt with regionally and insect conditions are reported on a
district basis. Insects and diseases currently causing minor damage are listed
alphabetically in tabular form.
The Dutch elm disease continued to spread throughout the southern part of the
North Bay District and an increase in the intensity of infection occurred in the
Parry Sound District. White pine blister rust and Hypoxylon canker of poplar
continued to cause appreciable mortality in the region. Damage by the needle cast
Lophodermerium pinastri (Schad. ex Fr.) was widespread on red pine trees throughout
the Parry Sound District. Late spring frosts caused conspicuous damage to white
spruce and balsam-fir trees at numerous locations. Windbreaks and roadside trees
were damaged by salt spray at several points in the Parry, Sound District.
The most notable change in forest insect conditions in 1965 was the increase
in area of infestation of the forest tent caterpillar. A total of 1500 square
miles of severe defoliation occurred in the Muskoka Lakes and Lake Nipissing
infestations. High populations of the poplar leaf roller Pseudexentera oregonana
Wlshm, within the infested areas made aerial mapping difficult. Population levels
of the red-headed pine sawfly increased in 1965 and pine plantations were severely
defoliated at many points in the Parry Sound District.
A total of 685 insect and disease samples were submitted and 111 service and
extension calls were answered during the field season. Short courses of instruction
on forest insects and tree diseases were given to junior forest rangers at 11
Department of Lands and Forests camps in the region.
L. S. MacLeod