Michigan Forest Communities - Michigan Association of ...

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Northern Pine and Oak Barrens
R
Habitat
These diverse communities sometimes
are separated into pine and oakpine
barrens, but in reality they share
many characteristics, occur in similar
habitats, occupy comparable geographic
areas, and often intergrade. They typically
occur on flat or gently rolling outwash
plains, lake plains, and sand
dunes. Soils in these xeric or dry-mesic
habitats are sandy, acid in pH, relatively
infertile, and seasonally droughty.
Barrens are the open savanna analog of
dry-mesic oak (Type 10) and dry northern
jack pine (Type 12) forests. The
unique plant community of these barrens—in
essence treed prairies—is
maintained by frequent fires or by frost
in depressions where cold air drains.
The exact composition and structure of
these communities vary by habitat conditions,
past history, and geography
from south to north and east to west.
Some barrens once dominated by pine
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