Ohio subset of Plant Communities of the Midwest ... - NatureServe

Wooded Swamps and Floodplains: Midwestern Wet Flatwoods
Quercus palustris - Quercus bicolor - Acer rubrum Flatwoods Forest
Pin Oak - Swamp White Oak - Red Maple Flatwoods Forest
Northern (Great Lakes) Flatwoods
CEGL005037
DESCRIPTION: Deciduous hardwoods and softwoods predominate. Diagnostic species include Quercus bicolor,
Quercus ellipsoidalis, Quercus palustris, and Acer rubrum. Other associates include Ilex verticillata and Ulmus
americana. The herbaceous layer, which can be sparse, contains Carex muskingumensis, Glyceria striata,
Maianthemum canadense, Mitchella repens, and Osmunda cinnamomea (White and Madany 1978, Homoya et al.
1988, Pat Comer pers. comm. 1997).
This type is found on glaciated plains in the midwestern United States. This community occurs on poorly drained
uplands or in depressions on level glacial lakeplains or outwash plains. There is a layer of acidic sand over a layer of
impermeable or nearly impermeable clay resulting in a shallow, perched water table. Ponding is common during the
wet seasons. In the dry months, the clay layer prevents water from moving up to the surface by capillary action from
deeper, more moist soil. Thus, the soil moisture fluctuates widely over the year (White and Madany 1978, Homoya et
al. 1988).
Given that fire was probably common in adjacent landscapes, flatwoods may have experienced fire during drought
periods and contained a more open canopy. Some may have supported a prairie flora prior to onset of fire
suppression (White and Madany 1978).
COMMENTS: 2, MCS. This type is found on glaciated plains in the Midwest. The terms "swamp" and "flatwoods" may
overlap (see e.g., Lee et al. 1998, who include flatwoods types in their swamp category). These terms need
clarification. In Indiana, stands may also be related to the lakeplain oak opening type, Quercus macrocarpa - Quercus
palustris - Quercus bicolor / Calamagrostis canadensis Wooded Herbaceous Vegetation (CEGL005120). In Michigan
this type occurs only in Calhoun County. Ontario sands on the clayplain of the Niagara Peninsula should be
compared with Fagus grandifolia - Acer saccharum - Quercus bicolor - Acer rubrum Flatwoods Forest
(CEGL005137).
CONSERVATION RANK: G2G3. There are probably fewer than 100 occurrences of this community rangewide. It is
reported from Ohio (where it is ranked S3), Indiana (S2), Illinois (S2), Ontario (S), and Michigan (S). Currently
there are 19 occurrences documented from Illinois, Indiana, Ohio, and Michigan. This community has moderately
restricted environmental requirements. Many sites of this community have been drained or cleared.
DISTRIBUTION: This pin oak - swamp white oak flatwoods community type is found in the midwestern United States
and Canada near Lake Michigan and Lake Erie, ranging from northern Illinois, northern Indiana, northern Ohio, and
southeastern Michigan, to southern Ontario.
USFS ECOREGIONS: 221Fb:CCC, 222Ha:CCC, 222Hb:CCC, 222Ia:CCC, 222If:CCC, 222Jb:CCC, 222Jh:CCC, 222Ji:CCC,
222Jj:CCC, 222Kf:CCC, 222Kg:CCC, 222Kj:CCC
CONSERVATION REGIONS: 45:C, 46:C, 48:C, 49:C
STATES: IL IN MI OH PROVINCES: ON
MIDWEST HERITAGE SYNONYMY: IL northern flatwoods =
IN boreal flatwoods =
MI pin oak depression +
OH oak-maple swamp +
OTHER SYNONYMY:
USNVC HIERARCHY: QUERCUS PALUSTRIS - (QUERCUS BICOLOR) SEASONALLY FLOODED FOREST ALLIANCE (I.B.2.N.e)
PLANT COMMUNITIES OF THE MIDWEST – 2001. APPENDIX: ASSOCIATION DESCRIPTIONS
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