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<br />Dry Prairie is a dry to dry-mesic herbaceous community dominated by grasses and sedges. It
<br />occurs throughout the prairie zone and sporadically in the deciduous forest - woodland zone. Dry
<br />Prairie has considerable variation in species composition, reflecting interactions among
<br />geography (namely climate), soils, and topography. In general, Dry Prairies have a greater
<br />component of Great Plains species than Mesic Prairies, especially in prairies in the western part
<br />of Minnesota. Big bluestem (Andropogon gerardii) is always present in the community and
<br />usually important, but it does not achieve the dominance it typically has in Mesic Prairie.
<br />Indiangrass (Sorghastrum nutans) is more limited in occurrence, generally appearing only where
<br />conditions approach mesic. Mid - height and short grasses and sedges are usually dominant in Dry
<br />Prairie. Among the more common are porcupine grass (Stipa spartea), little bluestem
<br />(Schizachyrium scoparium), side -oats grama (Bouteloua curtipendula), prairie June -grass
<br />(Koeleria macrantha), and sun - loving sedge (Carex heliophila).
<br />Forb variation within the community is more pronounced. Some widespread, characteristic
<br />species are dotted blazing star (Liatris punctata), pasque flower (Pulsatilla nuttalliana), prairie
<br />golden -aster (Heterotheca villosa), stiff sunflower (Helianthus rigidus), silky aster (Aster
<br />sericeus), green milkweed (Asclepias viridora), stiff goldenrod (Solidago rigida), gray
<br />goldenrod ( Solidago nemoralis), Missouri goldenrod (Solidago missouriensis), and narrow -
<br />leaved puccoon (Lithospermum incisum). Dry Prairies share many forb species with Mesic
<br />Prairies, including rough blazing star ( Liatris aspera), buffalo -bean (Astragalus crassicarpus),
<br />tooth - leaved evening primrose (Calylophus serrulatus), silverleaf scurfpea (Psoralea
<br />argophylla), thimbleweed (Anemone cylindrica), Louisiana sagewort (Artemisia ludoviciana),
<br />prairie larkspur (Delphinium virescens), heart- leaved alexanders (Zizia aptera), purple prairie -
<br />clover (Petalostemon purpureum), hoary puccoon (Lithospermum canescens), prairie smoke
<br />(Geum trorum), and wood lily (Lilium philadelphicum).
<br />Three sub - shrubs -- leadplant (Amorpha canescens), prairie rose (Rosa arkansana), and wolfberry
<br />(Symphoricarpos occidentalis) -- typical in Mesic Prairies are also generally present in Dry
<br />Prairie. Soil - encrusting lichens and the fern-ally rock - spikemoss (Selaginella rupestris) are often
<br />common in Dry Prairie. Brush, and sometimes trees, may be present in hollows and draws. Bur
<br />oak (Quercus macrocarpa), chokecherry (Prunus virginiana), wild plum (Prunus americana),
<br />and smooth sumac (Rhus glabra) are the most widespread woody species. Other woody species
<br />more limited in distribution in the community are northern pin oak (Quercus ellipsoidalis), black
<br />oak (Quercus velutina), and hazel (Corylus americana).
<br />Dry Prairies are maintained by fire but require less frequent fires than mesic and wet prairies
<br />because the droughty conditions within Dry Prairies slow or prevent the growth of woody
<br />species. Dry Prairie occurs on a variety of landforms, including sand dune blankets of mid -
<br />Holocene origin, glacial lake beach ridges, outwash deposits, ice - contact features (kames,
<br />eskers), morainic hills, erosional slopes in glacial drift, and bedrock -cored bluffs. Soils range
<br />from nearly pure sand with little profile development, to mollisols, although the latter have a
<br />much thinner organic -rich surface horizon than the soils of Mesic Prairie. All overlie deep glacial
<br />drift except for those of the bedrock -cored bluffs, which are formed in a thin layer of loess or
<br />residuum. Soils are well drained to excessively drained. Depending upon the degree of slope, the
<br />slope aspect, and the soil composition, Dry Prairie intergrades with Mesic Prairie.
<br />The Preserve Conservation Development - Restoration and Management Plan 17
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