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The shrub and herb pollen and the low influx rate in pollen zone 9 indicated that following deglaciation, there were not many trees present. This was a shrub tundra environment that was cold and wet. Poplar and aspen began to grow in pollen zone 8 in noticeable numbers but the influx rate does not suggest any forests, but a parkland type of vegetation. In pollen zone 7 spruce replaces poplar and aspen. A closed forest is not yet suggested by the influx rates but it does suggest that the trees grew in clumps. The main factor at this time for limiting growth of a forest is the cool climatic conditions and also incomplete soil development. In pollen zone 6 the increase in jack, birch, and red pine as well as oak, blue beech, ironwood, and maple led to the formation of a closed forest. There were major climatic changes around 10,000 years before present. Changes in the forest occurred approximately 1500 years before present, although the changes in the last 3000 years were not as drastic until logging and settlement in the 1800's.
The Champlain sea may have prevented plant migration until 10,200 years before present. Paper birch replaced spruce after 9,800 to 9,500 years ago. White pine increased and replaced other pines and reached a maximum at 6,500 years ago, but was then replaced by hemlock. Beech replaced hemlock as the hemlock declined around 3,200 years ago. |
 Ophioglossum vulgatum |
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