-36- 
is bordered by a rocky cliff. In this case the area above 
is often forested to the very edge of the cliff. On account 
of the dip of the strata, such areas are so well drained that 
the vegetation becomes xerophytic in character. This was 
found to bo true even where the soil was 3 dra. deep as was 
observed at one point. At this point the ridge had once been 
covered by a growth of pine, which had been blown dawn, and 
was being followed by a growth of white birch, aspen and 
balsam, the two formwr being on the lake side, being better 
able to adapt themselves to the unusually severe wind con- 
f 
ditions. 
2. Secondary successions in the hemlock climax. 
In the latter part of the summer of 1919, 
an extensive fire swept over a portion of the north range, 
destroying several square miles of virgin hemlock forest. 
This fire extended as far east as the range line between town¬ 
ships 42 and 43. The conffers were killed outright, though 
many dead trunks were left standing (fig. 22). It was very 
evident that the deciduous trees, including the sugar maple 
and especially basswood, were more resi stant to the effects 
of the fire than the conifers. This was especially trtioeable 
in the zone between the burned and unburned areas, where the 
trees were singed. Fig. 22 shows how thoroughly the humus 
