Forest Insect and Disease Survey; Ontario, 1965 - NFIS

D 32
Black-headed Jack-pine Sawfly, Neodiprion pratti banksianae (Roh.)
Two centres of infestation were observed in 1965. The upper crowns of jack
pine trees in the Mozhabong Lake area were severely defoliated for the fourth consecutive
year and a light infestation persisted along the Chapleau River in D'Arcy
Township. Scattered colonies were observed in several townships in the southern part
of the district.
The preferred hosts were jack pine trees along river banks and on rocky, exposed
sites.
Red-headed Jack-pine Sawfly, Neodiprion virginianus complex
Larval colonies of this sawfly were commonly collected at 18 locations south
of a line running from the settlement of Missanabie in the northwestern part of
the district to Brutus Township on the Wrong Lake Road (see map). Observations in
the district as a whole indicated that an increase in population levels occurred
in 1965. However, the number of colonies recorded at permanent sampling stations
declined (Table 10).
In a small area near the Wakami River jack pine reproduction was stripped of
old foliage and pockets of light infestation occurred at the north end of Biscotasing
Lake in Smuts Township. Individual trees were severely defoliated in the
central part of the district notably in Chapleau and 13G townships.
TABLE 10
Summary of Red-headed Jack-pine Sawfly Larval Colony Counts
in the Chapleau District from 1963 to 1965
Note: Ten trees having a d.b.h. of 1" to 3" were examined at each location.
46 0.1 0. 4 0.2
Brutus 0.3
Panet 0.1 0 0
28 0.2 0 0
12F 0 0.6 0
11D 0. 1 0 0
11G 0.2
Wakami 1.7 0.8
4WD
9E 1.0
Margaret DUD VDD
1.8