Natural Succession
Natural succession, also known as ecological succession, is the
process by which
biological
communities replace
each other in a
relatively
predictable
sequence, based on
environmental
changes that occur
within the habitat.
Gradually, a climax,
or final community,
is established and
could remain in
perpetuity until
another disturbance,
such as fire,
agriculture or
glaciation, returns
the habitat to a
relatively barren
state.
A typical sequence in succession is
bare soil being
colonized by annual
grasses and forbs.
This pioneer
community is
gradually replaced
by woody vegetation
- first shrubs, then
fast-growing
shade-intolerant
trees, such as
conifer trees,
aspens and birch,
and eventually
shade-tolerant,
slower-growing
maples, basswood,
and elm. A
climax community,
however, is not an
unchanging community
and older trees
mature and die off
producing snags and
logs which can
provide their own
microhabitats. When
a forest reaches
this state it is
referred to as an
old-growth forest.
Here at Anoka-Ramsey, the receding
glaciers of the
Wisconsin glaciation
12,000 years ago
left a barren soil
along the
Mississippi River
called the
Anoka Sand Plain.
An open oak and
prairie habitat was
maintained in this
area by fire set by
Native Americans and
lightning strikes
until about the
1600s when a cooler,
moister climate
reduced the
frequency of fires.
This allowed the Big
Woods to replace the
prairie with maples,
American elm, and
basswood, though
patches of prairie
and oak savanna
still remained.
Europeans brought their own form of
disturbance as they
cleared woods for
timber and plowed
prairies for
agriculture.
The Big Woods was
broken up into
smaller fragments
and woodlots. When
Anoka-Ramsey bought
the property on
which it stands now,
the land was mostly
plowed field with
small woodlots and
shelterbelts. (see
aerial photos). The
northern part of the
property was set
aside for a Natural
Area and has been
allowed to succeed,
for the most part
unimpeded, except a
small portion being
managed for prairie.
As one compares the
aerial photos, one
can see the increase
in areas with trees
between 1960, 1977
and 2006.
Further
documentation can be
seen with
ground photos.
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© 2013 Anoka-Ramsey Community College - Biology Department.
The contents of this page have not been reviewed by ARCC.
Last Updated -August 12, 2016
Comments or Problems contact:
Melanie Waite-Altringer or
Joan McKearnan or
Terry Teppen
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