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Diphasiastrum tristachyum

(Pursh) Holub

Deep-root Clubmoss

G5Secure Found in 13 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
UnknownThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.159196
Element CodePPLYC01130
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomPlantae
PhylumLycophyta
ClassLycopodiopsida
OrderLycopodiales
FamilyLycopodiaceae
GenusDiphasiastrum
Synonyms
Lycopodium tristachyumPursh
Other Common Names
Blue Ground-cedar (EN) deeproot clubmoss (EN) Deep-root Ground-pine (EN) Lycopode à trois épis (FR) Three-spiked Clubmoss (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
FNA (vol. 2, 1993) transfers Lycopodium tristachyum to Diphasiastrum tristachyum.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2024-08-09
Change Date1984-04-16
Edition Date2024-08-09
Edition AuthorsM.E. Stover, TNC-HO, 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
Diphasiastrum tristachyum is a clubmoss occurring in dry, sandy soils of conifer forests and woodlands, in edges, thickets, clearings, rocky slopes, barrens, and abandoned fields of eastern North America in the United States and Canada, Europe, and Asia. There are over 900 estimated occurrences of this species, which are threatened by development, road maintenance, invasive species, logging, and other threats in some places. With a large range extent, high number of occurrences, abundant habitat, broad habitat preferences, and no obvious intrinsic vulnerabilities, this species is considered secure.
Range Extent Comments
Diphasiastrum tristachyum occurs in eastern North America from Manitoba east to Newfoundland, Canada, and New York and Maine south to Georgia, west to Missouri, and north to Michigan and Minnesota in the United States (FNA 1993). This species' range also includes Europe and Asia in western China. Range extent was estimated to be over 23 million square kilometers using herbarium specimens and photo-based observations documented between 1993 and 2024 (GBIF 2024, iNaturalist 2024, SEINet 2024).
Occurrences Comments
By applying a 1 km separation distance to herbarium records and photo-based observations documented between 1993 and 2024, there are estimated to be over 900 occurrences rangewide (GBIF 2024, iNaturalist 2024, SEINet 2024).
Threat Impact Comments
Although threats are not widely documented, Diphasiastrum tristachyum is threatened by development, road maintenance, invasive species, logging, and other threats in some places (NatureServe 2024). However, their overall impact is likely negligible given the 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

Diagnostic Characteristics

Ultimate branchlets not flattened in cross section, usually bluish glaucous; underside leaves approximately equal in size to upperside leaves (L. complanatum and L. digitatum have the branchlets flattened and the underside leaves much reduced); strobili stalked (L. alpinum and L. sitchense have the strobili sessile or on short stalks); horizontal stems deeply buried (all four named above have the horizontal stems either on the surface or shallowly buried). Hybridizes with L. complanatum, L. digitatum, and L. sitchense, and rarely with L. alpinum. (FNA 1993)

Habitat

In North America, Diphasiastrum tristachyum occurs in dry, often sandy, often acid soils in coniferous woods, open oak or conifer forests, edges, thickets, clearings, rocky slopes, dry barrens, and abandoned fields (Cody and Britton 1989, Fernald 1950, FNA 1993, Gleason and Cronquist 1991, Hough 1983, Lellinger 1985, Radford et al. 1968, Roland and Smith 1983).

Reproduction

Diphasiastrum tristachyum is sporophytic and spores are dispersed by wind.The tiny gametophytes are subterranean and mycorrhizal, and bear the male and female gametes in separate but contiguous organs.
Terrestrial Habitats
Forest - HardwoodForest - ConiferWoodland - ConiferShrubland/chaparralOld fieldBarrensBare rock/talus/scree
Other Nations (2)
CanadaN5
ProvinceRankNative
OntarioS5Yes
Prince Edward IslandS3Yes
Island of NewfoundlandS5Yes
ManitobaS3Yes
QuebecS5Yes
New BrunswickS4Yes
Nova ScotiaS4Yes
United StatesN5
ProvinceRankNative
New HampshireSNRYes
KentuckyS4Yes
Rhode IslandSNRYes
MaineSNRYes
VermontS5Yes
DelawareS2Yes
District of ColumbiaSNRYes
New JerseyS3Yes
MassachusettsSNRYes
ConnecticutSNRYes
IndianaS2Yes
PennsylvaniaS5Yes
GeorgiaS1Yes
North CarolinaS3Yes
WisconsinSNRYes
New YorkS5Yes
MichiganSNRYes
South CarolinaS1Yes
MinnesotaSNRYes
VirginiaS5Yes
TennesseeS3Yes
MarylandS3Yes
West VirginiaS4Yes
OhioSUYes
MissouriS1Yes
AlabamaS1Yes
Threat Assessments
ThreatScopeSeverityTiming
1 - Residential & commercial developmentUnknownUnknownUnknown
4 - Transportation & service corridorsUnknownUnknownUnknown
4.1 - Roads & railroadsUnknownUnknownUnknown
5 - Biological resource useUnknownUnknownUnknown
5.3 - Logging & wood harvestingUnknownUnknownUnknown
8 - Invasive & other problematic species, genes & diseasesUnknownUnknownUnknown
8.1 - Invasive non-native/alien species/diseasesUnknownUnknownUnknown
8.1.1 - Unspecified speciesUnknownUnknownUnknown

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Plant Characteristics
DurationPERENNIAL, EVERGREEN
Economic Value (Genus)No
Roadless Areas (13)
New Hampshire (2)
AreaForestAcres
PemigewassetWhite Mountain National Forest32,255
Presidential - Dry River ExtWhite Mountain National Forest10,555
North Carolina (3)
AreaForestAcres
Graveyard Ridge (addition)Pisgah National Forest1,958
Laurel MountainPisgah National Forest5,683
Middle Prong AdditionPisgah National Forest1,852
Virginia (5)
AreaForestAcres
Brush Mountain EastJefferson National Forest4,916
Kelley MountainGeorge Washington National Forest7,590
Little Wilson Creek Addition BJefferson National Forest1,725
Mill MountainGeorge Washington National Forest10,840
Three RidgesGeorge Washington National Forest4,745
West Virginia (3)
AreaForestAcres
Canaan LoopMonongahela National Forest7,867
Cranberry AdditionMonongahela National Forest11,123
Tea Creek MountainMonongahela National Forest8,295
References (13)
  1. Cody, W.J., and D.M. Britton. 1989. Ferns and fern allies of Canada. Research Branch, Agriculture Canada, Ottawa. 430 pp.
  2. Fernald, M. L. 1950. Gray's manual of botany. 8th edition. Corrected printing (1970). D. Van Nostrand Company, New York. 1632 pp.
  3. Flora of North America Editorial Committee (FNA). 1993a. Flora of North America north of Mexico. Vol. 2. Pteridophytes and gymnosperms. Oxford Univ. Press, New York. xvi + 475 pp.
  4. Gleason, H.A., and A. Cronquist. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. New York Botanical Garden, Bronx, New York. 910 pp.
  5. Global Biodiversity Information Facility (GBIF). 2024. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2024).
  6. Hough, M.Y. 1983. New Jersey wild plants. Harmony Press, Harmony, NJ. 414 pp.
  7. iNaturalist. 2024. Online. Available: https://www.inaturalist.org (accessed 2024).
  8. 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.
  9. Lellinger, D.B. 1985. A field manual of the ferns and fern-allies of the U.S. and Canada. Smithsonian Institution Press, Washington, DC. 389 pp.
  10. NatureServe. 2024. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  11. Radford, A.E., H.E. Ahles, and C.R. Bell. 1968. Manual of the vascular flora of the Carolinas. Univ. North Carolina Press, Chapel Hill, NC. 1183 pp.
  12. Roland, A.E., and E.C. Smith. 1983. The flora of Nova Scotia: Volumes 1 and 2. Nova Scotia Museum, Halifax, NS, Canada. 746 pp.
  13. Southwest Environmental Information Network (SEINet). 2024. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2024).