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Hypericum ascyron

L.

Great St. John's-wort

G5Secure Found in 1 roadless area NatureServe Explorer →
G5SecureGlobal Rank
UnknownThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.138496
Element CodePDCLU031E0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderMalpighiales
FamilyHypericaceae
GenusHypericum
Other Common Names
great St. Johnswort (EN) Millepertuis à grandes fleurs (FR)
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
Robson (2001) regards North American plants as a subspecies of Hypericum ascyron.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2024-06-20
Change Date2024-06-20
Edition Date2024-06-20
Edition AuthorsClemants, Steven E. (1986), rev. N. Ventrella (2024)
Threat ImpactUnknown
Range Extent>2,500,000 square km (greater than 1,000,000 square miles)
Number of Occurrences> 300
Rank Reasons
Hypericum ascyron is a widespread herb occurring in forests, streamsides, roadsides, fens, swamps, in moist to dry meadows, and on rocky or grassy slopes of eastern North America from Ontario to Québec, Canada, south to Maryland, and west to Kansas, United States. It is also found in Asia and Siberia. There are over 1,000 occurrences of this species, which are threatened by development, invasive species, recreation, erosion, changes to water levels, succession, and other threats in some places. Little is known about trends and threats to Asian and Russian subspecies, but with a large range extent, large number of occurrences, and no obvious intrinsic vulnerabilities, this species is considered secure.
Range Extent Comments
Hypericum ascyron occurs in eastern North America from Ontario east to Québec, Canada, south to Maryland, and west to Kansas, United States (Flora of North America Editorial Committee 2015). It also occurs in Asia in east China, Japan, Korea, and Siberia. Range extent was estimated to be 4.4 million square kilometers using herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1993 and 2024 (GBIF 2024, iNaturalist 2024, NatureServe 2024, SEINet 2024). See individual entries for distribution details about the three subspecies.
Occurrences Comments
By applying a 1 km separation distance to herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1993 and 2024, it is estimated that there are over 1,600 occurrences rangewide (GBIF 2024, iNaturalist 2024, NatureServe 2024, SEINet 2024).
Threat Impact Comments
Although threats are not widely documented, Hypericum ascyron in North America is threatened by development, invasive species, recreation, erosion, changes to water levels, succession, and other threats in some places (NatureServe 2024). Threats to Asian and Russian subspecies are currently unknown. However, their overall impact is likely negligible given species' broad range, large number of occurrences, tolerance of light disturbance, and affinity for typically abundant habitats, as well as no obvious intrinsic vulnerabilities.
Ecology & Habitat

Habitat

Hypericum ascyron occurs in forests among scrub, streamsides, in roadside ditches, fens, swamps, in moist to dry meadows, and on rocky or grassy slopes (Flora of North America Editorial Committee 2015, Wu et al. 2007, Weakley and the Southeastern Flora Team 2024), from sea level to 2800 (-3600) m in elevation (Wu et al. 2007).
Terrestrial Habitats
Forest/WoodlandForest EdgeGrassland/herbaceousBare rock/talus/scree
Palustrine Habitats
FORESTED WETLANDBog/fenRiparian
Other Nations (2)
CanadaN3
ProvinceRankNative
OntarioS3Yes
QuebecSNRYes
United StatesN5
ProvinceRankNative
MassachusettsS1Yes
OhioSNRYes
VermontS2Yes
IllinoisSNRYes
MissouriSNRYes
KansasSNRYes
MinnesotaSNRYes
NebraskaSNRYes
PennsylvaniaSNRYes
MaineS1Yes
MichiganSNRYes
ConnecticutS2Yes
IowaSNRYes
DelawareSNRYes
New JerseySNRYes
WisconsinSNRYes
West VirginiaS1Yes
New HampshireSNRYes
New YorkS3Yes
IndianaSNRYes
Threat Assessments
ThreatScopeSeverityTiming
1 - Residential & commercial developmentUnknownUnknownUnknown
6 - Human intrusions & disturbanceUnknownUnknownUnknown
6.1 - Recreational activitiesUnknownUnknownUnknown
7 - Natural system modificationsUnknownUnknownUnknown
7.1 - Fire & fire suppressionUnknownUnknownUnknown
7.1.2 - Suppression in fire frequency/intensityUnknownUnknownUnknown
7.2 - Dams & water management/useUnknownUnknownUnknown
8 - Invasive & other problematic species, genes & diseasesUnknownUnknownUnknown
8.1 - Invasive non-native/alien species/diseasesUnknownUnknownUnknown
8.1.1 - Unspecified speciesUnknownUnknownUnknown
9 - PollutionUnknownUnknownUnknown
9.3 - Agricultural & forestry effluentsUnknownUnknownUnknown
9.3.2 - Soil erosion, sedimentationUnknownUnknownUnknown

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Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)No
Roadless Areas (1)
Wisconsin (1)
AreaForestAcres
09159 - ThornappleChequamegon-Nicolet National Forest9,744
References (9)
  1. Flora of North America Editorial Committee (FNA). 2015. Flora of North America north of Mexico. Vol. 6. Magnoliophyta: Cucurbitaceae to Droserceae. Oxford University Press, New York. 496 pp + xxiv.
  2. Global Biodiversity Information Facility (GBIF). 2024. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2024).
  3. iNaturalist. 2024. Online. Available: https://www.inaturalist.org (accessed 2024).
  4. 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.
  5. NatureServe. 2024. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  6. Robson N.K.B. 2001. Studies in the genus <i>Hypericum</i> L. (Guttiferae) 4(1). Sections 7.<i> Roscyna </i>to 9. <i>Hypericum sensu lato</i> (part 1). Bull. Nat. Hist. Mus. London, Bot. 31(2): 37-88
  7. Southwest Environmental Information Network (SEINet). 2024. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2024).
  8. Weakley, A.S., and Southeastern Flora Team. 2023. Flora of the southeastern United States. Edition of April 14, 2023. University of North Carolina Herbarium (NCU), North Carolina Botanical Garden, University of North Carolina, Chapel Hill. 2105 pp.
  9. Wu, Z. Y., P. H. Raven & D. Y. Hong, eds. 2007. Flora of China. Vol. 13 (Clusiaceae through Araliaceae). Science Press, Beijing, and Missouri Botanical Garden Press, St. Louis.