Print Report
CEGL002596 Thuja occidentalis / Carex eburnea - Pellaea atropurpurea Cliff Woodland
Type Concept Sentence: No Data Available
Common (Translated Scientific) Name: Northern White-cedar / Bristleleaf Sedge - Purple Cliffbrake Cliff Woodland
Colloquial Name: Appalachian Northern White-cedar Cliff Woodland
Hierarchy Level: Association
Type Concept: This white-cedar cliff woodland type is found in the Appalachian and Allegheny Plateau region of the United States. The type extends to near the southern limit of Thuja occidentalis, in the southeastern Highland Rim of Kentucky and Tennessee, where it tends to increase its distinctiveness from more northern communities. Stands occur on north-facing bluffs or cliffs of dolomite or limestone, where dip slopes provide slight seepage and maintain humidity higher than the regional average, or provide a cooler-than-normal microclimate. In Ohio it occurs as pure isolated patches on steep calcareous cliffs. It is also found as mixed stands on the uplands above the cliffs. Stands are dominated by coniferous trees but can have a significant amount of deciduous species. The structure of this association can vary from a stunted, very open canopy of Thuja to a mixed conifer-deciduous woodland approaching a forest structure. Canopy species other than Thuja occidentalis vary with geography. The most abundant tree species are Thuja occidentalis, Acer saccharum, Tsuga canadensis, Juniperus virginiana, Quercus alba, Quercus muehlenbergii, and Quercus rubra. Other associates include Celtis occidentalis and Ulmus rubra in more northern stands. Shrub and small tree species include Cercis canadensis, Cornus florida, Hydrangea arborescens, Ostrya virginiana, and Rhus aromatica. Closed-canopy stands have very few vascular species in the lower strata, while stands with broken canopies contain scattered shrubs and a substantial number of herbaceous species. Composition of the herbaceous and shrub strata can also vary due to seepage influence. Composition is quite variable, but some of the most constant herbaceous plants include Asarum canadense, Carex eburnea, Cystopteris bulbifera, and Hepatica nobilis var. acuta. In Kentucky, sites are small (0.1-1 acre), with scattered Thuja occidentalis codominating with Acer saccharum, Fraxinus americana, Ostrya virginiana, and Philadelphus hirsutus. Other associated species include Juniperus virginiana var. virginiana, Cercis canadensis var. canadensis, Pachysandra procumbens, Hamamelis virginiana, Parthenocissus quinquefolia, Solidago flexicaulis, Solidago sphacelata, Symphyotrichum cordifolium, and Dioscorea quaternata. Examples occurring along the C&O Canal in the Maryland Ridge and Valley have rather sparse vegetation, with plants growing from crevices or on shallow soil on ledges. Woody vegetation is composed of stunted trees, with Thuja occidentalis, Ostrya virginiana, Ulmus rubra, and Acer saccharum most frequent. Hydrangea arborescens is a characteristic and frequent shrub, with Ribes cynosbati less constant. Scrambling vines of Toxicodendron radicans and/or Parthenocissus quinquefolia are often present. The most frequent herbaceous species are Cystopteris bulbifera, Sedum ternatum, Aquilegia canadensis, Asplenium trichomanes, Asplenium rhizophyllum, Eurybia divaricata, Heuchera americana, Arabis laevigata, Arabis hirsuta, Pilea pumila, Polymnia canadensis, Solidago caesia, and various herbaceous species of shaded, rocky limestone forests. Pellaea atropurpurea is occasionally present but is absent from many examples and is more characteristic of xeric calcareous cliffs in Maryland.
Diagnostic Characteristics: No Data Available
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: This type is simply defined by the presence of white-cedar or mixed white-cedar - hardwoods, and either forest or woodland canopy; hence all four physiognomic categories fall under this one type. Small-scale occurrences are worth documenting. The relationship between this type and ~Thuja occidentalis / Carex eburnea Forest (CEGL006021)$$ should be examined and clarified. Stands on lower slopes often grade into swamps, especially those dominated by Thuja occidentalis. There are also many similarities between this vegetation and that in the ~Thuja occidentalis Acidic Forest Alliance (A3252)$$. In the Ridge and Valley of Virginia, Thuja occidentalis communities occur in two situations: on rocky bluffs with admixtures of hardwood species and on mesic slopes with Tsuga canadensis and Pinus strobus (G. Fleming pers. comm. 1999). Southern Thuja stands are more genetically diverse than northern populations (Walker 1987). One Tennessee site is a proposed State Natural Area, Window Cliffs. This association is peripheral in the Southern Blue Ridge of Tennessee.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: No Data Available
Floristics: Stands are dominated by coniferous trees, but with a significant amount of deciduous species. The most abundant tree species are Thuja occidentalis, Acer saccharum, Tsuga canadensis, Juniperus virginiana, Quercus alba, Quercus muehlenbergii, and Quercus rubra. Other associates include Quercus coccinea and Liriodendron tulipifera in more southern stands, and Celtis occidentalis and Ulmus rubra in more northern stands. Where soils are deeper, hardwoods generally do better. Shrub and small tree species include Cercis canadensis, Cornus florida, Hydrangea arborescens, Ostrya virginiana, and Rhus aromatica. Closed-canopy stands have very few vascular species in the lower strata, while stands with broken canopies contain scattered shrubs and a substantial number of herbaceous species. Composition is quite variable, but some of the most constant herbaceous plants include Asarum canadense, Carex eburnea, Cystopteris bulbifera, and Hepatica nobilis var. acuta (= Hepatica acutiloba) (Anderson 1996). In Kentucky, Thuja occidentalis occurs within the Cumberland River drainage in the southeastern Highland Rim region. These woodlands are associated with steep, rocky, limestone, mostly north- and east-facing slopes along permanent streams. Some stands are associated with cold-air drainages. These sites are small (0.1-1 acre), with scattered Thuja occidentalis codominating with Acer saccharum, Fraxinus americana, Ostrya virginiana, and Philadelphus hirsutus. Other associated species include Juniperus virginiana var. virginiana, Cercis canadensis var. canadensis, Pachysandra procumbens, Hamamelis virginiana, Parthenocissus quinquefolia, Solidago flexicaulis, Solidago sphacelata, Symphyotrichum cordifolium (= Aster cordifolius), and Dioscorea quaternata.
This vegetation type is represented in Virginia by open woodlands and sparse scrub occurring on nearly vertical limestone cliffs and their adjacent uplands above. Because these habitats cannot be fully accessed or plot-sampled, composition is described from qualitative examination of two stands. The dominant woody species is Thuja occidentalis. In the observed stands, specimens of this tree are shrubby and mostly <6 m tall. Associated woody species include Hydrangea arborescens and stunted individuals of Celtis tenuifolia, Cercis canadensis, Physocarpus opulifolius, Tilia americana (including both var. americana and var. heterophylla), and Ulmus rubra. Vines of Parthenocissus quinquefolia and Toxicodendron radicans are abundant climbers on rock faces at both sites. Carex eburnea is the most conspicuous, if not the most abundant, herbaceous species, forming dense turfs on ledges. Constant herbs in the two stands are Aquilegia canadensis, Asplenium resiliens, Asplenium rhizophyllum, Carex eburnea, Cystopteris bulbifera, Draba ramosissima, Eurybia divaricata (= Aster divaricatus), Pellaea atropurpurea, and Sedum glaucophyllum. Of these, Eurybia divaricata, Cystopteris bulbifera, and Sedum glaucophyllum are relatively abundant locally.
This vegetation type is represented in Virginia by open woodlands and sparse scrub occurring on nearly vertical limestone cliffs and their adjacent uplands above. Because these habitats cannot be fully accessed or plot-sampled, composition is described from qualitative examination of two stands. The dominant woody species is Thuja occidentalis. In the observed stands, specimens of this tree are shrubby and mostly <6 m tall. Associated woody species include Hydrangea arborescens and stunted individuals of Celtis tenuifolia, Cercis canadensis, Physocarpus opulifolius, Tilia americana (including both var. americana and var. heterophylla), and Ulmus rubra. Vines of Parthenocissus quinquefolia and Toxicodendron radicans are abundant climbers on rock faces at both sites. Carex eburnea is the most conspicuous, if not the most abundant, herbaceous species, forming dense turfs on ledges. Constant herbs in the two stands are Aquilegia canadensis, Asplenium resiliens, Asplenium rhizophyllum, Carex eburnea, Cystopteris bulbifera, Draba ramosissima, Eurybia divaricata (= Aster divaricatus), Pellaea atropurpurea, and Sedum glaucophyllum. Of these, Eurybia divaricata, Cystopteris bulbifera, and Sedum glaucophyllum are relatively abundant locally.
Dynamics: No Data Available
Environmental Description: This community is found primarily on steep calcareous cliffs, as well as on the uplands above the cliffs. The bedrock is typically limestone or dolomite (Braun 1928, Anderson 1996). Soils are shallow, dry, and calcareous, and plants often root in crevices or on narrow ledges, or adjacent clifftops and talus. In Ohio this woodland community occurs as pure, isolated patches on steep calcareous cliffs. It is also found as mixed stands on the uplands above the cliffs. The site of a glacial relict stand in Ohio is maintained by seepage springs from underground limestone formations (Kangas 1989). In Kentucky Thuja occidentalis occurs within the Cumberland River drainage in the southeastern Highland Rim region. These woodlands are associated with steep, rocky, limestone, mostly north- and east-facing slopes along permanent streams. Some stands are associated with cold-air drainages.
In Virginia the type is evidently confined to north-facing cliffs and escarpments produced by incision of high-order streams and rivers into carbonate bedrock of the Ridge and Valley province. Often situated on steep cut-slopes on the outside bends of stream meanders, habitats are more-or-less open but have limited solar exposure because of their north aspects. Microtopography is rugged and complex, encompassing sheer faces, ledges, and crevices of variable configuration. Slopes range from 40-90° and exposed bedrock constitutes >90% of the surface substrate. Substrate moisture regime is generally subxeric but is ameliorated to some degree by frequent zones of ephemeral seepage and by sheltered north aspects that slow evaporation.
In Virginia the type is evidently confined to north-facing cliffs and escarpments produced by incision of high-order streams and rivers into carbonate bedrock of the Ridge and Valley province. Often situated on steep cut-slopes on the outside bends of stream meanders, habitats are more-or-less open but have limited solar exposure because of their north aspects. Microtopography is rugged and complex, encompassing sheer faces, ledges, and crevices of variable configuration. Slopes range from 40-90° and exposed bedrock constitutes >90% of the surface substrate. Substrate moisture regime is generally subxeric but is ameliorated to some degree by frequent zones of ephemeral seepage and by sheltered north aspects that slow evaporation.
Geographic Range: This white-cedar cliff woodland type is found in the Appalachian and Allegheny Plateau regions of the United States.
Nations: US
States/Provinces: KY, MD, OH, TN, VA, WV
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.686389
Confidence Level: Moderate
Confidence Level Comments: No Data Available
Grank: G2G3
Greasons: No Data Available
| Type | Name | Database Code | Classification Code |
|---|---|---|---|
| Class | 1 Forest & Woodland Class | C01 | 1 |
| Subclass | 1.B Temperate & Boreal Forest & Woodland Subclass | S15 | 1.B |
| Formation | 1.B.2 Cool Temperate Forest & Woodland Formation | F008 | 1.B.2 |
| Division | 1.B.2.Na Eastern North American Forest & Woodland Division | D008 | 1.B.2.Na |
| Macrogroup | 1.B.2.Na.2 Appalachian-Northeastern Oak - Hardwood - Pine Forest & Woodland Macrogroup | M502 | 1.B.2.Na.2 |
| Group | 1.B.2.Na.2.b Chinquapin Oak - White Ash - Eastern Red-cedar Forest & Woodland Group | G016 | 1.B.2.Na.2.b |
| Alliance | A3914 Northern White-cedar Appalachian Limestone Cliff Woodland Alliance | A3914 | 1.B.2.Na.2.b |
| Association | CEGL002596 Northern White-cedar / Bristleleaf Sedge - Purple Cliffbrake Cliff Woodland | CEGL002596 | 1.B.2.Na.2.b |
Concept Lineage: CEGL006278 merged with CEGL003631 which was subsequently merged into CEGL002596.
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: = Thuja occidentalis / Carex eburnea - Pellaea atropurpurea Woodland (Faber-Langendoen 2001)
> Thuja occidentalis / Carex eburnea - Sedum glaucophyllum Shrubland (Fleming 1999)
> Thuja occidentalis / Carex eburnea - Sedum glaucophyllum Woodland (Fleming and Coulling 2001)
= Arbor vitae forest (Braun 1928)
> Thuja occidentalis / Carex eburnea - Sedum glaucophyllum Shrubland (Fleming 1999)
> Thuja occidentalis / Carex eburnea - Sedum glaucophyllum Woodland (Fleming and Coulling 2001)
= Arbor vitae forest (Braun 1928)
- Anderson, D. M. 1996. The vegetation of Ohio: Two centuries of change. Draft. Ohio Biological Survey.
- Braun, E. L. 1928. The vegetation of the Mineral Springs region of Adams County, Ohio. The Ohio State University Bulletin, Volume 32, No. 30. Ohio Biological Survey, Bulletin 15. 3(5):383-517.
- Faber-Langendoen, D., editor. 2001. Plant communities of the Midwest: Classification in an ecological context. Association for Biodiversity Information, Arlington, VA. 61 pp. plus appendix (705 pp.).
- Fleming, G. P. 1999. Plant communities of limestone, dolomite, and other calcareous substrates in the George Washington and Jefferson national forests, Virginia. Natural Heritage Technical Report 99-4. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond. Unpublished report submitted to the USDA Forest Service. 218 pp. plus appendices.
- Fleming, G. P., K. D. Patterson, and K. Taverna. 2017. The natural communities of Virginia: A classification of ecological community groups and community types. Third approximation. Version 3.0. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA. [http://www.dcr.virginia.gov/natural-heritage/natural-communities/]
- Fleming, G. P., and K. D. Patterson. 2009b. Classification of selected Virginia montane wetland groups. In-house analysis, December 2009. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond.
- Fleming, G. P., and P. P. Coulling. 2001. Ecological communities of the George Washington and Jefferson national forests, Virginia. Preliminary classification and description of vegetation types. Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA. 317 pp.
- Fleming, Gary P. Personal communication. Ecologist, Virginia Department of Conservation and Recreation, Division of Natural Heritage, Richmond, VA.
- Harrison, J. W. 2011. The natural communities of Maryland: 2011 working list of ecological community groups and community types. Unpublished report. Maryland Department of Natural Resources, Wildlife and Heritage Service, Natural Heritage Program, Annapolis. 33 pp.
- Harrison, J. W., compiler. 2004. Classification of vegetation communities of Maryland: First iteration. A subset of the International Classification of Ecological Communities: Terrestrial Vegetation of the United States, NatureServe. Maryland Natural Heritage Program, Maryland Department of Natural Resources, Annapolis. 243 pp.
- Kangas, P. 1989. Comparison of two northern white cedar (Thuja) forests. The Michigan Botanist 28:59-68.
- Midwestern Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Minneapolis, MN.
- ONHD [Ohio Natural Heritage Database]. No date. Vegetation classification of Ohio and unpublished data. Ohio Natural Heritage Database, Division of Natural Areas and Preserves, Ohio Department of Natural Resources, Columbus.
- Palmer-Ball, B., Jr., J. J. N. Campbell, M. E. Medley, D. T. Towles, J. R. MacGregor, and R. R. Cicerello. 1988. Cooperative inventory of endangered, threatened, sensitive and rare species, Daniel Boone National Forest, Somerset Ranger District. USDA Forest Service, Daniel Boone National Forest, Berea, KY. 244 pp.
- TDNH [Tennessee Division of Natural Heritage]. 2018. Unpublished data. Tennessee Division of Natural Heritage, Nashville, TN.
- WVNHP [West Virginia Natural Heritage Program]. No date. Unpublished data. West Virginia Natural Heritage Program, Elkins.
- Walker, G. L. 1987. Ecology and population biology of Thuja occidentalis L. in its southern disjunct range. Ph.D. dissertation, University of Tennessee, Knoxville. 160 pp.