Forest Insect and Disease Survey; Ontario, 1965 - NFIS

C9
townships Haddo, Caldwell, Crerar, Gibbons, and Ratter and along the Sturgeon River
north of River Valley where pockets of light infestation were present in 1964. Few
sawflies were found on Lake Temagami where colonies were common on islands and
shoreline stands in 1963 and 1964.
TABLE 11
Summary of Red-pine Sawfly Larval Colony Counts at Five Points
in the North Bay District 1964 and 1965
Note: Counts were based on the examination of 10 trees at each point.
Location
township
Tree species
No. of trees
infested
16 1965
Av. no. colonies per
infested tree
1 6 1965
Cynthia rP 10 1 2 Ratter rP 5 1 2 McNish
jP 6 2 3 1
Joan rP 6 2 0 0
Afton jP 10 2 0 0
Swaine Jack-pine Sawfly, Neodi rion swainei (Midd.)
Light infestations of this sawfly recurred on small islands in Banks and Rabbit
lakes. Repeated defoliation has caused extensive mortality to jack-pine trees on
two islands in Rabbit Lake. Light mortality occurred on one island in Lake Temagami
where trees have been heavily infested for several years. Scattered colonies were
observed along the West Arm of Lake Nipissing and on islands in Lake Temagami in
Cynthia, Joan, Briggs and Strathcona townships.
White Pine Weevil, Pissodes strobi (Peck)
High population levels of the white pine weevil persisted in pine stands
throughout the district. Extensive leader damage to white pine reproduction occurred
in cut-over tracts in the upper Sturgeon River area and in plantations at many
locations through the district (Table 12).
TABLE 12
Summary of Leader Damage by the White Pine Weevil at Four Points
in the North Bay District in 1965
Note: Counts were based on the examination of 100 trees at each point.
Location Tree Av. height Per cent of trees Cumulative per cent of trees
townshi s ecies in feet weevilled in l' 6 weevilled all -ars
French jP 13 6 25
Widdifield wP 12 18 40
Gibbons scP 15 8 38
Afton wP 16 12 48