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Scutellaria saxatilis

Riddell

Rock Skullcap

G3Vulnerable (G3G4) Found in 5 roadless areas NatureServe Explorer →
G3VulnerableGlobal Rank
High - mediumThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.157864
Element CodePDLAM1U150
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single nation
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderLamiales
FamilyLamiaceae
GenusScutellaria
Other Common Names
smooth rock skullcap (EN) Smooth Rock Skullcap (EN)
Concept Reference
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Taxonomic Comments
Excludes var. pilosior (= Scutellaria arguta).
Conservation Status
Rank MethodLegacy Rank calculation - Excel v3.1x
Review Date2018-08-30
Change Date2018-08-30
Edition Date2018-08-30
Edition AuthorsAmbrose, Donn M.(1994); rev. S.L.Neid (1998); rev. L. Morse (2000), rev. C. Nordman (2018)
Threat ImpactHigh - medium
Range Extent200,000-2,500,000 square km (about 80,000-1,000,000 square miles)
Number of Occurrences81 - 300
Rank Reasons
Scutellaria saxatilis is an Appalachian, clonal, perennial plant which occurs in rocky forests. At least 125 occurrences are known from eight of ten states across the range of the species where information is available. This species is considered sufficiently common that it is not tracked in a few states, but it is rare nearly everywhere else. It is apparently most abundant in Virginia and Kentucky.
Range Extent Comments
Scutellaria saxatilis only occurs in the Eastern United States, primarily in the Appalachians from Delaware, Maryland and southwestern Pennsylvania to southern Indiana, south to east Tennessee, and western North Carolina.
Occurrences Comments
There are an estimated 125 extant occurrences in Indiana (3), Kentucky (7), Maryland (4), North Carolina (14), Ohio (20), Pennsylvania (6), Tennessee (46), and West Virginia (21). It also occurs in Virginia (individual populations not documented, but it has been found in 26 counties).
Threat Impact Comments
This species is subject to drying by sunlight if large gaps of openings are present in the forest canopy. The primary threat is loss of forest canopy (affects the moist microclimate of forest floor). The invasion of exotic species is a threat (including Microstegium vimineum, Japanese Stilt Grass; Ailanthus altissima, Tree of heaven, and Lonicera japonica, Japanese Honeysuckle). Other threats include grazing, and recreational use of habitat (trampling of plants at a popular site in Maryland).
Ecology & Habitat

Habitat

Scutellaria saxatilis occurs in rich, often rocky, deciduous woods. It is associated with rocky woods of sandstone and shale, on hillsides, moist cliffs, talus slopes, in mesophytic ravines, moist areas along streams, but is sometimes found in dry woods or more open habitat, such as along roadsides (Dolan 2004).
Terrestrial Habitats
Forest - Hardwood
Other Nations (1)
United StatesN3
ProvinceRankNative
District of ColumbiaSNRYes
TennesseeS3Yes
KentuckyS2Yes
New JerseySNRYes
West VirginiaS3Yes
IndianaS1Yes
AlabamaS1Yes
VirginiaS3Yes
North CarolinaS2Yes
South CarolinaSXYes
MarylandS1Yes
OhioS2Yes
DelawareSHYes
GeorgiaS1Yes
PennsylvaniaS1Yes
Threat Assessments
ThreatScopeSeverityTiming
1 - Residential & commercial developmentSmall (1-10%)Moderate or 11-30% pop. declineHigh (continuing)
2 - Agriculture & aquacultureSmall (1-10%)Moderate or 11-30% pop. declineHigh (continuing)
2.3 - Livestock farming & ranchingSmall (1-10%)Moderate or 11-30% pop. declineHigh (continuing)
5 - Biological resource useRestricted (11-30%)Serious - moderateHigh (continuing)
5.3 - Logging & wood harvestingRestricted (11-30%)Serious - moderateHigh (continuing)
8 - Invasive & other problematic species, genes & diseasesRestricted (11-30%)Moderate or 11-30% pop. declineHigh (continuing)
8.1 - Invasive non-native/alien species/diseasesRestricted (11-30%)Moderate or 11-30% pop. declineHigh (continuing)
11 - Climate change & severe weatherSmall (1-10%)Slight or 1-10% pop. declineModerate (short-term)
11.4 - Storms & floodingSmall (1-10%)Slight or 1-10% pop. declineModerate (short-term)

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Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (5)
Tennessee (2)
AreaForestAcres
London Bridge BranchCherokee National Forest3,387
Sampson Mountain AdditionCherokee National Forest3,064
Virginia (2)
AreaForestAcres
Peters Mountain Addition A (VA)Jefferson National Forest1,268
Shawvers Run AdditionJefferson National Forest1,927
West Virginia (1)
AreaForestAcres
Peters Mountain Addition A (WV)Jefferson National Forest343
References (49)
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  2. Cusick, A. W. 1992. Botanist, Ohio Natural Heritage Program. Personal communication with D. Schuen, MI NFI: ESA questionnaire for Scutellaria saxatilis. 4 pp.
  3. Cusick, A.W. and G.M. Silberhorn. 1977. The vascular plants of unglaciated Ohio. The Ohio State University, Columbus, OH. Bulletin of the Ohio Biological Survey- New Series 5(4): 102.
  4. Daniel Boone National Forest. 1992. Cooperative inventory of endangered, threatened, sensitive, and rare species, Daniel Boone National Forest, Moorhead Ranger District. Cooperators: United States Forest Service, The Nature Conservancy, Kentucky State Nature Preserves Commission, Kentucky Department of Fish and Wildlife Resources. 34pp.
  5. Daniel Boone National Forest (DBNF). 1992. Cooperative inventory of endangered, threatened, sensitive, and rare species, Daniel Boone National Forest, Morehead Ranger District. Cooperators: United States Forest Service, The Nature Conservancy, Kentucky State Nature Preserves Commission, Kentucky Department of Fish and Wildlife Resources.
  6. Deam, C. C. 1940. Flora of Indiana. Division of Forestry, Dept. of Conservation, Indianapolis, Indiana. 1236 pp.
  7. Delaware Natural Heritage Program (DE NHP). 1993. Rare native plants of Delaware. Department of Natural Resources and Environmental Control, Division of Parks and Recreation.
  8. Delaware Natural Heritage Program (DE NHP). 1993. Rare native plants of Delaware. Department of Natural Resources and Environmental Control, Division of Parks and Recreation, Smyrna, DE.
  9. Dolan, R. 2004. Conservation Assessment for Rock Skullcap (Scutellaria saxatilis Riddell). USDA Forest Service, Eastern Region. Friesner Herbarium, Butler University. Indianapolis, IN.
  10. Fernald, M. L. 1950. Gray's Manual of Botany, 8th edition. American Book Company, New York.
  11. Fernald, M.L. 1970. Gray's manual of botany. 8th edition. 1970 printing with corrections by R.C. Rollins [of 1950 8th edition]. D. Van Nostrand Company, New York.
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  20. Homoya, M. 1992. Ecologist/Botanist, Indiana Natural Heritage Data Center. Personal communication with M. Penskar, MI NFI: ESA questionnaire for Scutellaria saxatilis. 4 pp.
  21. Indiana Natural Heritage Data Center (IN NHDC). 1994. Element occurrence records for <i>Scutellaria saxatilis</i>. 4 pp.
  22. Jacquart, E.M. 1992a. Botanist, Hoosier National Forest, Brownstown, IN. Field notes for Scutellaria saxatilis sites on the Ironton District. 2 pp.
  23. Jacquart, E.M. 1992b. Botanist, Hoosier National Forest, Brownstown, IN. Field notes for Scutellaria saxatilis sites on the Tell City District. 2 pp.
  24. Kartesz, J.T. 1993. Species distribution data for vascular plants of 70 geographical areas, from unpublished data files at the North Carolina Botanical Garden, July, 1993.
  25. Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
  26. Kentucky Natural Heritage Program (KY NHP). 1994a. Element ranking form for Scutellaria saxatilis. 3 pp.
  27. Kentucky Natural Heritage Program (KY NHP). 1994b. Element occurrence records for Scutellaria saxatilis. 4 pp.
  28. Ludwig, Chris. Botanist, Virginia Division of Natural Heritage, Department of Conservation and Recreation. Pers. comm. with M. Penskar, MI NFI: Letter. 2 pp.
  29. Maryland Natural Heritage Program (MDNHP). 1994g. Element state ranking form for Scutellaria saxatilis. 1 p.
  30. Maryland Natural Heritage Program (MDNHP). 1994h. Element occurrence records for Scutellaria saxatilis. 5 pp.
  31. McAvoy, W. 1992a. Botanist, Delaware Natural Heritage Program. Personal communication with M. Penskar, MI NFI: ESA questionnaire for Scutellaria saxatilis. 4 pp.
  32. McAvoy, W. 1992b. Botanist, Delaware Natural Heritage Program. Personal communication with M. Penskar, MI NFI: Herbarium label information for Scutellaria saxatilis. 1 p.
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  35. Ohio Natural Heritage Program (OH NHP). 1994a. Species summary sheet for <i>Scutellaria saxatilis</i>. 1 p.
  36. Ohio Natural Heritage Program (OH NHP). 1994b. Element occurrence records and LCD forms for <i>Scutellaria saxatilis</i>. 19 pp.
  37. Radford, A. E., H. E. Ahles, and C. R. Bell. 1964. Manual of the Vascular Flora of the Carolinas. University of North Carolina Press, Chapel Hill, North Carolina.
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  42. Southern Appalachian Species Viability Project. 2002. A partnership between the U.S. Forest Service-Region 8, Natural Heritage Programs in the Southeast, NatureServe, and independent scientists to develop and review data on 1300+ regionally and locally rare species in the Southern Appalachian and Alabama region. Database (Access 97) provided to the U.S. Forest Service by NatureServe, Durham, North Carolina.
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