Vol. 22 , No. 8 
Page 2 
more cavities than expected and were not extensively cut; white oak and walnut* 
the species most affected by logging, had significantly fewer cavities than 
expected. At Massac, tree cavities were distributed by species according to 
their abundance both before and after logging. 
Cull trees were not removed, thus ensuring that many trees containing 
cavities remained on each study area. 
Leaf nests were counted each fall on the Massac and Cole areas but not on 
the Old Barn area where leaf nests were scarce. Nests were classified as used 
or abandoned by squirrels according to nest integrity. 
Before logging at Cole, squirrels built leaf nests significantly more often 
in white oak, the hickories, and black oak than the abundance of these species 
would indicate; they built significantly less often in black walnut and elm. 
After logging, squirrels built significantly more nests than expected in sugar 
maple, a species not cut by loggers. Numbers of fall leaf nests at Cole declined 
after logging. At Massac, squirrel preference for leaf nest sites shifted from 
black oak before logging to shingle oak after logging. Significantly fewer nests 
than expected were built in sweet gum before and after logging on the Massac 
area. After logging, leaf nest construction at Massac increased only slightly, 
suggesting that shelter was not a significant problem for the resident squirrels* 
To study the effects of selection cutting on food supplies for squirrels, we 
determined the number of selected tree species needed to provide food for 2.5 
squirrels per ha (1 squirrel/acre) for 180 days (October-March). Data for this 
stocking guide were (1) the average seed production for major trees which produce 
winter-storeable food, and (2) recent information on food consumption by squirrels 
in winter. 
According to species abundance on the study areas, we assume that acorns 
comprise 50%, hickories 30%, and black walnut 10% of the fall and winter diet. 
We compared the postcutting abundance of these species on each area with our 
stocking guide. As shown in Table 1 , both Massac and Cole appear still to have 
an acceptable species mix of trees of seed-bearing size. Except for hickory, 
the Old Barn area did not have a good species mix after logging. Fortunately, 
the Old Barn area also supports 4 beeches, 7 red oaks, and 2 sugar maples per 
acre as supplements to the staple foods listed in Table 1 . Thus, logging did 
not appear to reduce food supplies to critically low levels on any of the study 
areas. 
We will consider ways to minimize the effects of selection cutting on 
squirrels in our next report. 
