Habitat Descriptions

C.E. Umbanhowar, Jr.'s revised "Vegetation of Wisconsin Habitats" as originally defined by J.T. Curtis (Wisconsin Plant Ecology Laboratory Data (PEL))

The descriptions under each major habitat type were written by Eric J. Epstein, Emmet J. Judziewicz, and Elizabeth Spencer of the Natural Heritage Inventory (NHI), Bureau of Endangered Resources, Wisconsin Department of Natural Resources for the forthcoming Habitat Database of Endangered, Theatened, and Special Concern Vascular Plants, and must be considered tentative.  They were condensed and summarized for the Curtis-Umbanhowar classification by Judziewicz.  Not all NHI type as currently recognized are included in the preliminary classification below.

Beech Forest  (Main Photo) (Photo directory)      (Wisconsin Plant Ecology Laboratory Data (PEL))
This forest type is present in eastern Wisconsin.  It was the dominant type in the counties along Lake Michigan, extending inland to western Waupaca, Shawano, and southern Forest Counties.  Beech (Fagus grandifolia) is the dominant tree, or is co-dominant with sugar maple (Acer saccharum), eastern hemlock (Tsuga canadensis), or (in the south) basswood (Tilia americana).  White white pine (Pinus strobus) and yellow birch (Betula allegheniensis), and those of the walnut family are other important tree species, especially in the north.  The groundlayer varies from rich and varied with fine spring ephemeral displays including species of dutchman's-breeches (Dicentra), trout-lily (Erythronium), spring-beauty (Claytonia), trillium (Trillium), violets (Viola), bloodroot (Sanguinaria canadensis), blue cohosh (Caulophyllum thalictroides) and mayapple (Podophyllum peltatum).  Often, especially in the north, the understory is poor with only a few dominants such as woodferns (especially Dryopteris intermedia), bluebead (Clintonia borealis) and Canada mayflower (Maianthemum canadense).  Indian cucumber-root (Medeola virginiana) and long spurred violet (Viola rostrata) are characteristic rare species.  After old-growth stands were cut, colonizing trees such as quaking and bigtoothed aspens (Populus tremuloides and P. grandidentata), white birch (Betula papyrifera) and red maple (Acer rubrum) became and still are important.

Tentatively included here are the following Wisconsin Natural Heritage Inventory types: parts of Northern Mesic Forest (in part) and Southern Mesic Forest (in part).

Bog[and Fen] (Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
This open wetland type is a catch-all category for a number of open peatlands that dominated by various combinations of sedges, sphagnum mosses, ericasceous shrubs, and insectivorous herbs.  Typically, true Open Bogs are confined to northern Wisconsin and are cold, acidic, weakly minerotrophic wetlands with no through-flow of nutrient rich water in the substrate; all water inflows as precipitation.  True bogs are dominated by Sphagnum spp. mosses that occur in deep layers with pronounced hummocks and swales. Also present are a few narrow-leaved sedge species such as Carex oligosperma and C. pauciflora, cotton-grasses (especially Eriophorum vaginatum subsp. spissum), and ericaceous shrubs, especially leatherleaf (Chamaedaphne calyculata).  Plant diversity is very low. Trees (mostly black spruce, tamarack, and white cedar) are absent or achieve very low cover values as this community is closely related and intergrades with Muskeg. If this community is found in southern Wisconsin, it is often referred to as a Bog Relict.  Here, poison-sumac (Toxicodendron vernix) is often formidably abundant in the understory, especially in the moat (or "lagg") at the upland/wetland interface.  A rare type of wetland in the state is Patterned Peatland, best-developed at Cedarburg Bog, Ozaukee County and characterized as a herb- and shrub-dominated minerotrophic peatland with alternating sedge-dominated peat ridges (strings) and hollows (flarks).  The flora is diverse and includes many sedges of bogs and fens, along with ericads, sundews, rare orchids, arrow-grasses (Triglochin spp.) and calciphilic shrubs such as bog birch (Betula pumila) and shrubby cinquefoil (Pentaphylloides floribunda).  Muskegs are cold, acidic, sparsely wooded northern wetlands with the same dominants as the Open Bogs (Sphagnum spp. mosses, Carex spp., and ericaceous shrubs), but with scattered stunted trees of black spruce (Picea mariana) and tamarack (Larix laricina). Plant diversity is low, but the community is important for a number of boreal bird and butterfly species.  Fen communities are minerotrophic, that is, there is percolating groundwater that carries nutrients through the system.  The flora is often rich and distinctive, including many forbs and graminoids, and a few characteristic shrub species such as bog birch, shrubby cinquefoil, and certain willos.  Calcareous Fens are related to Wet Prairies and occur throughout southern and eastern Wisconsin.  Boreal Rich Fens are rare and restricted to cold peatlands in the far north.  Coastal Fens are also rare, and are restricted to the estuaries of drowned river mouths along Lake Superior.  Central Poor Fens are restricted to the bed of old glacial Lake Wisconsin in the central part of the state.  They have floras of very low diversity, and are related to sedge meadows and open bogs.

Tentatively included here are the following Wisconsin Natural Heritage Inventory types: Open Bog, Bog Relict, Patterned Peatland, Muskeg (in part), Calcareous Fen, Boreal Rich Fen, Coastal Fen, and Central Poor Fen (in part).

Boreal Forest  (Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
In Wisconsin, mature stands are dominated by white spruce (Picea glauca) and balsam-fir (Abies balsamea), often mixed with white birch (Betula papyrifera), white cedar (Thuja occidentalis), white pine (Pinus strobus), balsam-poplar (Populus balsamifera) and quaking aspen (Populus tremuloides). Mountain-ash (Sorbus spp.) may also be present. Common understory herbs are large-leaved aster (Aster macrophyllus), bluebead (Clintonia borealis), Canada mayflower (Maianthemum canadense), wild sarsaparilla (Aralia nudicaulis) and bunchberry (Cornus canadensis).  This community is best developed along the Lake Superior coast, near the tip of the Door Peninsula on the Lake Michigan side, and in the northern tier of inland counties at higher elevations (above about 1,500 feet).

Bracken Grassland  (Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
These are open upland areas, often on sandy soils, of the northern one-third of the state.  They are dominated by bracken fern (Pteridium aquilinium), Penn sedge (Carex penyslvanica), Kalm's bromegrass (Bromus kalmii), and Canada bluegrass (Poa compressa). There may be a high cover of low shrubs such as blueberries (Vaccinium angustifolium and V. myrtilloides), sweet fern (Comptonia peregrina), prairie willow (Salix humilis), and hazelnuts (Corylus spp.). Other common forbs include poverty oat-grass (Danthonia spicata), Lindley's aster (Aster ciliolatus), gray goldenrod (Solidago nemoralis), and common strawberry (Fragaria virginiana). Exotics are often frequent. There is disagreement on whether bracken grassland should be considered a "natural community" in Wisconsin and elsewhere in the Upper Great Lakes region.

Cliff(Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
Cliff communities occur nearly throughout Wisconsin, and are divided into sunny, exposed types, and moist shaded types.
Exposed, thin-soiled, very dry communities occur on many different rock types and are quite varied in species composition. Scattered pines, oaks, or shrubs often occur. The ferns polypody (Polypodium virginianum) and rusty woodsia (Woodsia ilvensis) are often present, along with columbine (Aquilegia canadensis), harebell (Campanula rotundifolia), pale corydalis (Corydalis sempervirens), juneberry (Amelanchier spp.), bush-honeysuckle (Diervilla lonicera), rock spikemoss (Selaginella rupestris), and fringed bindweed (Polygonum cilinode).  Shaded moist to seeping mossy, lichened cliffs and ledges also occur on various rock types, most commonly sandstone and dolomite. Common species in this community are columbine, the fragile ferns (Cystopteris bulbifera,C. fragilis and others), wood ferns (Dryopteris spp.), polypody, rattlesnake-root (Prenanthes alba), and wild sarsaparilla (Aralia nudicaulis). The rare flora of these cliffs vary markedly in different parts of the state; Driftless Area cliffs might have northern monkshood (Aconitum columbianum var. columbianum), those on Lake Superior butterwort (Pinguicula vulgaris), or those in Door County green spleenwort (Asplenium trichamanes-ramosum).

Tentatively included here are the following Wisconsin Natural Heritage Inventory types: Dry Cliff, Moist Cliff.

Emergent Aquatic  (Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
These are marsh, lake, riverine and estuarine communities dominated by emergent macrophytes, often in pure stands. Dominants are often species of cat-tails (Typha spp.), bulrushes (particularly Schoenoplectus acutus, S. fluviatilis, and S. tabernaemontani), bur-reeds (Sparganium spp.), giant reed (Phragmites australis), pickerel-weed (Pontederia cordata), water-plantains (Alisma spp.), arrowheads (Sagittaria spp.), and the larger species of spikerush such as Eleocharis palustrisi and E. robbinsii. A subtype has wild rice (Zizania palustris) as a dominant.  In such stands, the substrate is usually poorly-consolidated, semi-organic sediments, water fertility is low to moderate, and currents are present but slow. Wild rice beds have cultural significance to native peoples, and are important wildlife habitats.

Northern Lowland Forest  (Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
A great variety of forested wetland types are included in this broad category.  Classic Curtisian Northern Wet Forest is a northern, weakly minerotrophic conifer swamp dominated by black spruce (Picea mariana) and tamarack (Larix laricina). Jack pine (Pinus banksiana) may be a significant canopy component in certain parts of the range of this community complex. Understories are composed mostly of Sphagnum spp. mosses and ericaceous shrubs such as leatherleaf (Chamaedaphne calyculata), Labrador-tea (Ledum groenlandicum), and small cranberry (Vaccinium oxycoccos).  This type grades into a very open stand intermediate to Open Bog (Muskeg), and to purer Black Spruce Swamps or Tamarack Swamps.   The former type has a poor groundlayer, while the latter type (which grades into an isolated southern subtype, Tamarack Fen) has a richer, minerotrophic calcareous understory.  In more well-drained sites, Northern Wet Forests are common.  These forested wetlands, often known simply as "cedar swamps," are dominated by white cedar (Thuja occidentalis), and occurs on rich, neutral to alkaline substrates. Balsam fir (Abies balsamea), black ash (Fraxinus nigra), and spruces (Picea glauca and P. mariana) are among the many potential canopy associates. The understory is rich in sedges (such as Carex disperma and C. trisperma), orchids, wildflowers such as goldthread (Coptis trifolia), fringed polygala (Polygala pauciflora), naked mitrewort (Mitella nuda), the trailing sub-shrubs twinflower (Linnaea borealis) and creeping snowberry (Gaultheria hispidula), and many species of orchids, some rare.  Floodplain Forests occur along large, periodically flooding rivers.  In the north several of these species are absent, but balsam-poplar (Populus balsamifera), box-elder (Acer negundo) and bur oak (Quercus macrocarpa) may occur instead.  Nettles (Laportea canadensis and Urtica dioica) and ostrich fern (Matteuccia struthiopteris) are dominant understory herbs.  Northern stands are often species poor, with box-elder a common canopy species.  A separate subtype are deciduous forests developed on rich, alluvial terraces along rich, infrequently flooding (or flooding only for a very short period) rivers draining into Lake Superior.  In these Mesic Floodplain Terraces, the dominant trees are usually black ash (Fraxinus nigra), green ash (F. pennsylvanica), basswood (Tilia americana), and sugar maple (Acer saccharum). There is a diverse spring ephemeral flora including many southern species at their northern range limits such as false-rue anemone (Enemion biternatum) and showy orchis (Galearis spectabilis).  White Pine - Red Maple Swamps are restricted to the margins of the bed of extinct glacial Lake Wisconsin in the central part of the state.  They often occurs along small rivulets and seeps in gradually sloping areas.  Pinus strobus and Acer rubrum are the dominant trees, with other species, including yellow birch, present in lesser amounts. Common understory shrubs are speckled alder (Alnus incana subsp. rugosa), winterberry holly (Ilex verticillata), and swamp dewberry (Rubus pubescens); frequent herbs are skunk cabbage (Symplocarpus foetidus) and cinnamon fern (Osmunda cinnamomea). Sphagnum spp. mosses are often common. The rare species Massachussetts fern (Thelypteris simulata) and long sedge (Carex folliculata) are locally frequent in some stands.

Tentatively included here are the following Wisconsin Natural Heritage Inventory types: Northern Wet Forest, Northern Wet-Mesic Forest ("Cedar Swamp"), Black Spruce Swamp, Tamarack Swamp, Tamarack Fen, Floodplain Forest (in part), Northern Hardwood Swamp, Mesic Floodplain Terrace, Muskeg (in part), and White Pine - Red Maple Swamp.

Northern Upland Forest  (Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
This forest type ranges from dry to mesic sites, with coniferous trees usually dominant.  Northern Dry Forests develop on nutrient-poor sites with excessively drained sandy or rocky soils. The primary historic disturbance regime was catastrophic fire, at intervals of decades to a century or so. Dominant trees of mature stands include jack and red pines (Pinus banksiana and P. resinosa) and Hill's oak (Quercus ellipsoidalis).  After catastrophic logging of the late 19th and early 20th centuries, large acreages supporting this forest type were cut and have been colonized by white birch (Betula papyrifera) and/or quaking aspen (Populus tremuloides), or converted in pine plantations starting in the 1920s.  Vast acreages of open "barrens" were also planted to pine, or naturally succeeded to densely stocked forests.  Common understory shrubs are early blueberry (Vaccinium angustifolium) and brambles (Rubus spp.); common herbs include bracken fern (Pteridium aquilinium), starflower (Trientalis borealis), wild sarsaparilla (Aralia nudicaulis), barren-strawberry (Waldsteinia fragarioides), cow-wheat (Melampyrum lineare), trailing arbutus (Epigaea repens), and members of the shinleaf family (Chimaphila umbellata, Pyrola spp.).  On rich sites, Northern Dry-Mesic Forests have pines mixed with red oak (Quercus borealis) and red maple (Acer rubrum).  Many of the understory shrubs are herbs are same as in the dry forest subtype.  Northern Mesic Forests dominated by sugar maple (Acer saccharum) and eastern hemlock (Tsuga canadensis), with white pine (Pinus strobus), beech (Fagus grandifolia),  yellow birch (Betula allegheniensis), and basswood (Tilia americana) also important.  The groundlayer varied from sparse (especially in pure hemlock stands) to rich and varied with fine spring ephemeral displays, but most commonly the dominants were woodferns (especially Dryopteris intermedia), bluebead (Clintonia borealis) and Canada mayflower (Maianthemum canadense). After old-growth stands were cut, colonizing trees such as quaking and bigtoothed aspens (Populus tremuloides and P. grandidentata), white birch (Betula papyrifera) and red maple (Acer rubrum) became and still are important in second-growth Northern Mesic Forests.  Mesic Cedar Forests are a rare upland community of mesic sites in northern Wisconsin, dominated by white cedar (Thuja occidentalis).

Tentatively included here are the following Wisconsin Natural Heritage Inventory types Nothern Dry Forest, Northern Dry-Mesic Forest, Northern Wet Forest, and Mesic Cedar Forest.

Pine Barrens (Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
This community is characterized by scattered small jack pines (Pinus banksiana) or less commonly red pines (P. resinosa), often mixed with scrubby Hill's oaks and bur oaks (Quercus ellipsoidalis and Q. macrocarpa), interspersed with openings in which shrubs (such as hazelnuts, Corylus spp.) and herbs dominate. The flora often contains species characteristic of "heaths" such as blueberries (Vaccinium angustifolium and V. myrtilloides), bearberry (Arctostaphylos uva-ursi), sweet fern (Comptonia peregrina), and fire cherry (Prunus pensylvanica).  In the central and far northwestern parts of the state, species of dry sand prairie species such as junegrass (Koeleria macrantha), little bluestem (Schizachyrium scoparium), asters (Aster sericeus and A. azureus), lupines (Lupinus perennis), and blazing-stars (Liatris spp.) are present.

Prairie(Main Photo) (Photo directory1) (Photo directory2)     (Wisconsin Plant Ecology Laboratory Data (PEL))
Prairies are grassland-dominated communities that occurred throughout the southern half of Wisconsin.  Most are now lost to agriculture and urbanization.  They were maintained by periodic natural (or human-caused) fires that reduced encroaching woody vegetation.  The few that remain are often restricted to linear strips along railroads where woody vegetation is periodically controlled.  Prairie subtypes range from Wet Prairie to Dry Prairie, according to soil moisture content.  In Wet Prairies, the dominant grasses are bluejoint (Calamagrostis canadensis) and cordgrass (Spartina pectinata), and sometimes very few true prairie species are present. Many of the forbs found in Wet-Mesic Prairies are also found in this community, plus the following species: New England aster (Aster novae-angliae), swamp thistle (Cirsium muticum), shooting-star (Dodecatheon meadia), black-eyed susan (Rudbeckia hirta), and mountain-mint (Pycnanthemum virginianum).   The dominant species of Wet-Mesic Prairies were big bluestem (Andropogon gerardii), bluejoint (Calamagrostis canadensis), cordgrass, and Canada wild-rye (Elymus canadensis).  Mesic Prairies occupied the richest soil and consequently are the rarest type, beacuse of conversion to agriculture.  The dominant plants are the grass big bluestem, little bluestem (Schizachyrium scoparium), Indian grass (Sorghastrum nutans), Needle grass (Stipa spartea), prairie dropseed (Sporobolus heterolepis), and side-oats grama (Bouteloua curtipendula).  The forb layer is diverse in the number, size and physiognomy of the species, and include the prairie docks (Silphium spp.), rattlesnake-master (Eryngium yuccifolium), and lowering spurge (Euphorbia corollata), as well as many asters, goldenrods, and sunflowers.  Dry-Mesic Prairies occur on slightly more xeric sites than have many of the same dominant grasses, except that big bluestem and Indian-grass are commoner than little bluestem.  The forb component is more diverse than in Dry Prairies, including many species that occur in both Dry and Mesic Prairies.  Dry Prairie often occurs on dry, often loess-derived soils, usually on south-facing slopes or at the summits of river bluffs with sandstone or dolomite near the surface. This subtype is frequent along the high bluffs ("Goat Prairies") of the Mississippi, Wisconsin, and lower Chippewa Rivers.  It is being encroached upon by red cedar (Juniperus virginiana) because of fire suppression.  Medium-sized prairie grasses are the dominants in this community: little bluestem, side-oats grama, prairie dropseed, and big bluestem. Common forbs include lead plant (Amorpha canescens), silky aster (Aster sericeus), flowering spurge), prairie-clovers (Dalea spp.) cylindrical blazing-star (Liatris cylindracea), and gray and stiff goldenrods (Solidago nemoralis and S. rigida).  So-called Sand Prairies develop on dry sandy soils where bedrock is not near the surface.  They are are dominated by little bluestem, junegrass (Koeleria macrantha), a panic grass (Panicum lanuginosum), and a crab grass (Digitaria cognata). Common herbaceous species are western ragweed (Ambrosia psilostachya), the sedges Carex muhlenbergii and C. pensylvanica, poverty-oat grass (Danthonia spicata), flowering spurge, frostweed (Helianthemum canadense), and common bush-clover (Lespedeza capitata).  Bedrock Glades are dry, sparsely vegetated non-vertical bedrock exposures on very thin soils. The rock type varies from quartzite (Baraboo Hills, McCaslin Mountain), to basalt (lower St. Croix River valley and Penokee Range), to granite (northeastern Wisconsin). The flora can include prairie, savanna, or barrens elements, some at their northern range limits. Trees and shrubs are sparse and may include pines, oaks, and cherries.

Tentatively included here are the following Wisconsin Natural Heritage Inventory types: Dry Prairie, Dry-Mesic Prairie, Sand Prairie, Mesic Prairie, Wet-Mesic Prairie, and Bedrock Glade (in part).

Sand Barrens(Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
Sand Barrens are best developed on unstable or semi-stabilized alluvial sand along major rivers such as the the Mississippi and Wisconsin Rivers. They are partly or perhaps wholly anthropogenic in origin, occurring in sites disturbed by plowing or very heavy past grazing. Blow-outs are characteristic. Barrens, Dry Prairie and Sand Prairie species are present in this community, such as false-heather (Hudsonia tomentosa), bearberry (Arctostaphylos uva-ursi), sedges (Cyperus filiculmis and C. schweinitzii), sand cress (Arabis lyrata), three-awn grasses (Aristida spp.), rock spikemoss (Selaginella rupestris), and the earthstar fungus (Geaster sp.). Many exotics are present, as well as rare species such as fameflower (Talinum rugospermum).

Sand Dunes [and Rocky Shorelines]   (Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
Wisconsin's Great Lakes shorelines have complex of distinctive natural communities.  The beach proper (Lake Beach) is a  dynamic community that is strongly influenced by water level changes and storms.  It supports a suite of very specialized organisms, although unprotected shorelines may be entirely unvegetated.  Some of the few plant species found in this community include (along Lake Michigan) seaside spurge (Chamaesyce olygonifolia) and American sea-rocket (Cakile edentula).  Just inland from the beach, is the Lake Dune.  The dominant plant is usually the sand-binding beachgrass (Ammophila breviligulata). Frequent associates are common juniper (Juniperus communis), Canada wild-rye (Elymus canadensis), false-heather (Hudsonia tomentosa), beach-pea (Lathyrus japonicus var. maritimus), beach wormwood (Artemisia campestris subsp. caudata), sand cherry (Prunus pumila), and various willows (Salix spp.). Pitcher's thistle (Cirsium pitcheri) and Lake Huron tansy (Tanacetum huronense; possibly now extirpated in Wisconsin) occur in this community.  Other associated community subtypes include Forested Ridge and Swale such at the Ridges, Door County; nutrient-poor sandstone Bedrock Beach such as on the Apostle Islands in Lake Superior; and flat, shelving, dolomitic Great Lakes Alkaline Rockshore such as on the Lake Michigan side of the Door Peninsula.  Inland Beaches occur rarely along the shores of naturally fluctuating lakes in interiro Wisconsin.  They may have rare species such as Fassett's locoweed (Oxytropis campestris var. chartacea) and alpine milk-vetch (Astragalus alpinus var. alpinus).

Tentatively included here are the following Wisconsin Natural Heritage Inventory types: Lake Beach, Lake Dune, Inland Dune, Great Lakes Beach, Forested Ridge and Swale, Bedrock Beach, Great Lakes Alkaline Rockshore.

Savanna(Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
Savannas are partially forested upland communities, where tree canopies do not exceed about 50% coverage.  They are often maintained by fire and have a strong prairie or barrens component in the understory.  Oaks, especially bur oak (Quercus macrocarpa) are the commonest trees.  The division of savannas and woodlands into subtypes is quite problematical.  The Cedar Glade subtype occurs on dry sandstone, quartzite, or less commonly dolomite exposures forested with red cedar (Juniperus virginiana), red maple (Acer rubrum) and black and bur oaks (Quercus velutina and Q. macrocarpa) may also be present. This "community" is usually (or always) the result of fire suppression of dry prairies, and in pre-settlement times it may have occurred only where extensive cliffs were present. Common herbaceous members are bluestem grasses and grama grasses (Andropogon spp. and Bouteloua spp.), and prickly-pear cactus (Opuntia compressa).  Oak Barrens have feature black oak (Quercus velutina) as the overwhelming dominant. Common herbs are lead plant (Amorpha canescens), hog-peanut (Amphicarpaea bracteata), flowering spurge (Euphorbia corollata), bracken-fern (Pteridium aquilinium), false Solomon's-seals (Smilacina racemosa and S. stellata), spiderwort (Tradescantia ohioensis), goat's-rue (Tephrosia virginiana), and lupine (Lupinus perennis).  Oak Openings have less than 50% tree canopy cover. Historically, they occurred on wet-mesic to dry sites. The few extant remnants are mostly on dry sites, with the mesic openings almost totally destroyed. Bur, white and black oaks (Quercus macrocarpa, Q. alba and Q. velutina) are dominant, often as large, open-grown trees. Shagbark hickory (Carya ovata) is sometimes present. American hazelnut (Corylus americana) is a common shrub, and the herblayer is similar to that of oak forests and dry prairies, with many of the same grasses and forbs present.  Oak Woodlands are intermediate between Oak Openings and Southern Dry Forests. The tree canopy is closed, but frequent low-intensity fires and, possibly (in pre-settlement times), browsing by herbivores such as elk, bison, and deer, kept the understory free of shrubs and saplings.

Tentatively included here are the following Wisconsin Natural Heritage Inventory types: Cedar Glade, Oak Barrens, Oak Opening, Oak Woodland, and Bedrock Glade (in part).

Sedge Meadow  (Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
Sedge medows are open wetlands dominated by sedges and grasses.  There are several common subtypes: Tussock meadows, dominated by tussock sedge (Carex stricta) and the grass bluejoint (Calamagrostis canadensis); Broad-leaved sedge meadows, dominated by the robust sedges Carex lacustris and C. utriculata; and Wire-leaved sedge meadows, dominated by such species as woolly sedges (Carex lasiocarpa and C. pellita) and few-seeded sedge (C. oligosperma). Also frequent are marsh bluegrass (Poa palustris), manna grasses (Glyceria spp.), panicled aster (Aster lanceolatus), joy-pye-weed (Eupatorium maculatum), and the bulrushes Scirpus atrovirens and S. cyperinus.

Tentatively included here are the following Wisconsin Natural Heritage Inventory types: Northern Sedge Meadow, Central Poor Fen (in part), Southern Sedge Meadow.

Shrub Carr(Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
This type includes wetlands dominated by tall shrubs.  In northern Wisconsin, the commonest subtype is the Alder Thicket, dominated by thick growths of speckled alder (Alnus incana subsp. rugosa).  The herbaceous understory is frequently very diverse, and common species include Canada bluejoint (Calamagrostis canadensis), orange jewelweed (Impatiens capensis), several asters (Aster lanceolatus, A. puniceus, and A. umbellatus), boneset (Eupatorium perfoliatum), meadowsweet (Spiraea alba), marsh fern (Thelypteris palustris), arrow-leaved tearthumb (Polygonum sagittatum), and sensitive fern (Onoclea sensibilis).  Shrub-Carr proper is primarily a southern wetland community.  It is dominated by the tall shrub red-osier dogwood (Cornus stolonifera), but meadow-sweet (Spiraea alba) and various willows (Salix discolor, S. bebbiana, and S. gracilis) are frequently also important. Canada bluejoint is often very common. Other herbs are those found in Alder Thickets and tussock-type Sedge Meadows.

Tentatively included here are the following Wisconsin Natural Heritage Inventory types: Alder Thicket and Shrub-Carr.

Southern Lowland Forest  (Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
This is a lowland hardwood community that occurs along large, periodically flooding rivers.  Canopy dominants typically include silver maple (Acer saccharinum), river birch (Betula nigra), green ash (Fraxinus pennsylvanica), hackberry (Celtis occidentalis), swamp white oak (Quercus bicolor), and cottonwood (Populus deltoides).  Buttonbush (Cephalanthus occidentalis) is a locally dominant shrub.  Nettles (Laportea canadensis and Urtica dioica) and ostrich fern (Matteuccia struthiopteris) are dominant understory herbs, and lianas such as Virginia creepers (Parthenocissus spp.), grapes (Vitis spp.), Canada moonseed (Menispermum canadense), and poison-ivy (Toxicodendron radicans) are common. Characteristic herbs of this community are green-headed coneflower (Rudbeckia laciniata), cardinal flower (Lobelia cardinalis), green dragon (Arisaema dracontium), and false dragonhead (Physostegia virginiana). Floodplain Forest replaces, in part, the Southern Wet Forest of the Curtis community classification, but it may also occur well north of the Tension Zone.  Southern Hardwood Swamp is a subtype found in insular basins with seasonally high water tables.  It is best developed in glaciated southeastern Wisconsin.  The dominant trees are red maple (Acer rubrum), green ash, and American elm (Ulmus americana).  The exotic reed canary grass (Phalaris arundinacea) is often dominant in the understory. This Natural Heritage Inventory community partly includes the Southern Wet-Mesic Forest of the Curtis classification.

Tentatively included here are the following Wisconsin Natural Heritage Inventory types: Floodplain Forest (in part) and Southern Hardwood Swamp.

Southern Upland Forest  (Main Photo) (Photo directory)     (Wisconsin Plant Ecology Laboratory Data (PEL))
These southern Wisconsin forests are dominated by oaks and maples.  In Southern Dry Forest, white oak (Quercus alba) and black oak (Q. velutina) are dominant, often with admixtures of red and bur oaks (Q. borealis and Q. macrocarpa), and black cherry (Prunus serotina).  In the shrub layer, brambles (Rubus spp.), gray dogwood (Cornus racemosa) and American hazelnut (Corylus americana) are common.  Frequent herbaceous species are wild geranium (Geranium maculatum), false Solomon's-seal (Smilacina racemosa), hog-peanut (Amphicarpaea bracteata), sweet cicely (Osmorhiza claytonii) and Penn sedge (Carex pensylvanica).  In the Southern Dry-Mesic Subtype, red oak is the dominant tree, but white oak, basswood (Tilia americana), sugar maple (Acer saccharum), and white ash (Fraxinus americana) are also frequent.  The herbaceous understory flora is more diverse and includes those species listed under Southern Dry Forest plus jack-in-the-pulpit (Arisaema triphyllum), enchanter's-nightshade (Circaea lutetiana), and large-flowered bellwort (Uvularia grandiflora).  Southern Mesic Forest occurs on rich, well-drained soils.  The dominant trees species are sugar maple and basswood.  Many other trees species are found in these forests, including those of the walnut family (Juglandaceae). The understory is typically open (brushy with species of gooseberry [Ribes] if there is a past history of grazing) and supports fine spring ephemeral displays with species of spring-beauty (Claytonia), trout-lilies (Erythronium), trilliums (Trillium), violets (Viola), bloodroot (Sanguinaria canadensis), blue cohosh (Caulophyllum thalictroides) and mayapple (Podophyllum peltatum).  Central Sands Pine-Oak Forests are restricted to poor, acid sandy soils in the bed of old glacial Lake Wisconsin.  The dominants are white and red pines (Pinus strobus and P. resinosa), oaks (Q. alba, Q. borealis, and Q. velutina), and red maple. The understory is a sparse to dense layer of shrubs and coarse herbs: huckleberry (Gaylussacia baccata), early blueberry (Vaccinium angustifolium), bracken fern (Pteridium aquilinium), and wood anemone (Anemone quinquefolia).

Tentatively included here are the following Wisconsin Natural Heritage Inventory types: Southern Dry Forest, Southern Dry-Mesic Forest, Southern Mesic Forest, Central Sands Pine-Oak Forest.