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

Rocky Uplands (Glades, Rock Barrens, Outcrops and Alvars): Interior Highlands Shale
Glades and Barrens
Quercus marilandica - (Juniperus virginiana) / Schizachyrium scoparium - Danthonia spicata
Wooded Herbaceous Vegetation
Blackjack Oak - (Eastern Red-cedar) / Little Bluestem - Poverty Oatgrass Wooded Herbaceous
Vegetation
Central Shale Glade
CEGL002428
DESCRIPTION: Trees can be found scattered or in isolated clumps and patches throughout the occurrence, along
with a few saplings and shrubs. Quercus marilandica and Quercus stellata are the dominant trees (Quercus prinus is
dominant in Indiana examples), and Pinus virginiana or other Quercus spp. may also be found in some examples.
Vaccinium arboreum, Rhus aromatica and Ulmus alata are common shrubs. Vaccinium pallidum and Gaylussacia
baccata are common in Indiana examples. Ohio stands also contain Cercis canadensis, Amelanchier arborea,
Frangula caroliniana (= Rhamnus caroliniana), Rosa carolina, and Vaccinium stamineum. Schizachyrium scoparium
and Danthonia spicata dominate the herbaceous layer, along with a diverse assemblage of forbs. Missouri examples,
where the shales are fairly 'limey,' contain Astragalus distortus, Dalea purpurea, Porteranthus stipulatus, and
Psoralidium tenuiflorum. The herbaceous flora of Indiana Interior Low Plateau examples (Siltstone Glades) includes
Agalinis sp., Symphyotrichum patens (= Aster patens), Symphyotrichum shortii (= Aster shortii), Brickellia
eupatorioides (= Kuhnia eupatorioides), Cunila origanoides, Dichanthelium depauperatum, Euphorbia corollata,
Helianthus sp., Hypericum crux-andreae, Hypericum hypericoides, Liatris squarrosa, Manfreda virginica,
Porteranthus stipulatus, Schizachyrium scoparium, and Tephrosia virginiana. Some woody plants recorded at these
sites include Pinus virginiana, Quercus prinus, Quercus stellata, Quercus marilandica, and Juniperus virginiana. In
Ohio, Carex hirsutella, Agrostis perennans, Allium cernuum, Sericocarpus asteroides (= Aster paternus), Agalinis
tenuifolia (= Gerardia tenuifolia), Houstonia canadensis (= Hedyotis canadensis), and Lithospermum canescens,
among others, may occur. Some grasses and forbs from the Ouachita Mountain examples include Agrostis elliottiana,
Oenothera linifolia, Astragalus distortus, and Ruellia humilis. Lichens and mosses occur in profusion on exposed
bedrock surfaces and on soils not covered with organic debris (leaf litter, wood) (White and Madany 1978, Nelson
1985, Homoya 1994, TNC 1995a, D. Minney pers. comm. 2000).
In Missouri, this community occurs on moderate to steep slopes of dissected drainages along major streams and
mounds, and shales have a strong limestone component, making them less acid. In several square km of Illinois, a
series of steep ridges occurs in thick shale outcrops. Shale glades occur there on exposed slopes. The soil of these
communities is absent to thin (0-40 cm) and somewhat rapidly to very rapidly drained. The parent material is shale,
with siltstone present in Indiana occurrences. Shale fragments and exposed bedrock are common on the surface. In
Ohio, sites occur sparingly on estill shales with extreme southwestern exposures (White and Madany 1978, Nelson
1985, Homoya 1994, D. Minney pers. comm. 2000).
Rapid weathering and erosion on steep slopes appear to be necessary for shale glades to persist. Fires may have
been very occasional (Nelson 1985).
COMMENTS: 2, MCS. This community has a restricted distribution and occurrences are small. In Indiana, Quercus
prinus is the major dominant. Similar communities occur in West Virginia, and also with Quercus prinus as the
primary scattered tree. In the Knobs region of Kentucky this community is threatened by strip mining. Total vegetative
cover may sometimes be less than 10%. Shale glades in Missouri are so lime-rich that they may be treated as a
variant of limestone glade (M. Leahy pers. comm. 1999). In Ohio, areas of shale that have been plowed have come
back as "cedar barrens" but are typically dominated by a variety of annuals (though most of these are present at
some level in the natural shale glades as well), and these areas may resemble the more annual grassland type,
Sporobolus (vaginiflorus, neglectus, ozarkanus) - Aristida longispica - Panicum flexile - Panicum capillare
Herbaceous Vegetation (CEGL004340) described for Tennessee glades. These shale glades may be so depauperate
at this time that they could simply be combined with Quercus stellata - Quercus marilandica / Schizachyrium
scoparium - Silphium terebinthinaceum Wooded Herbaceous Vegetation (CEGL005134) (D. Minney pers. comm.
2000).
CONSERVATION RANK: G2. The shale glade community has a very restricted distribution and occurrences are small.
In Kentucky, where it is most abundant, particularly in the Knobs Region, threats are primarily from strip-mining, since
oil shales may be strip-mined depending on the market. Sites in Ohio have been disturbed by agriculture through
pasturing (but no clearing), severe erosion, or fire suppression.
PLANT COMMUNITIES OF THE MIDWEST – 2001. APPENDIX: ASSOCIATION DESCRIPTIONS
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