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- Diphasiastrum digitatum
Diphasiastrum digitatum — southern ground-cedar
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Facts
Southern ground-cedar is the most common ground-cedar in New England, and it is often used for decoration in wreaths. Another common name for this species is 'fan clubmoss,' which nicely describes the branches that are arranged in fan-like sprays.
Habitat
Anthropogenic (man-made or disturbed habitats), forest edges, forests, meadows and fields
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
Characteristics
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Leaf shape
- the vegetative leaves are short and scale-like
- Spore leaf arrangement
- the sporophylls are located on spore cones at the tips of the shoots or branches
- Form of shoot
- the plant has an upright stem, with branches, those branches having further branches, and so on (tree-like)
- Horizontal stem
- the horizontal stem is on the surface of the ground
- Leaf differences
- the vegetative leaves within a node differ in size and shape
- Teeth on leaf edges
- the edges of the vegetative leaves have no teeth
- Constriction zones
-
- there are constricted zones on the horizontal stem where the leaves are smaller smaller or closer together
- there are constricted zones on the vertical stem where the leaves are smaller smaller or closer together
- Spore leaf length
- 1.7–2.6 mm
- Leaf outline
-
- the vegetative leaves are widest above the base, then taper narrowly towards the tip (lanceolate)
- the vegetative leaves are long and very narrow (linear)
- the vegetative leaves are roughly triangular, widest at the base where the leaf joins the stem
-
Clonal plantlets
- Gemma arrangement
- NA
- Gemma shape
- NA
- Gemma width
- 0 mm
-
Leaves
- Leaf differences
- the vegetative leaves within a node differ in size and shape
- Leaf length
- 0.3–5.5 mm
- Leaf orientation
-
- the vegetative leaves are pressed against the stem
- the vegetative leaves spread away from the stem
- the vegetative leaves spread slightly away from the stem, at a steep angle
- Leaf outline
-
- the vegetative leaves are widest above the base, then taper narrowly towards the tip (lanceolate)
- the vegetative leaves are long and very narrow (linear)
- the vegetative leaves are roughly triangular, widest at the base where the leaf joins the stem
- Leaf ranks
- 4
- Leaf shape
- the vegetative leaves are short and scale-like
- Pores on leaves
- there are pores, but only on the underside of the vegetative leaves
- Spore leaf length
- 1.7–2.6 mm
- Teeth on leaf edges
- the edges of the vegetative leaves have no teeth
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- edges of forests
- forests
- man-made or disturbed habitats
- meadows or fields
-
Spores or spore cones
- Cone base at stem
- the base of the spore-cone has a distinct stalk
- Cone stalk branching
- the stalks bearing the spore cones are branched, with pairs of branches
- Cone thickness
- 0.6–1 mm
- Cone width
- 2–3 mm
- Length of cone
- 14–40 mm
- Number of cones
- 2–4
- Quillwort itssue covering spores
- NA
- Same or different spores
- there is only one type of spore present
- Spore girdle
- NA
- Spore leaf arrangement
- the sporophylls are located on spore cones at the tips of the shoots or branches
- Spore leaf lifespan
- the sporophylls wither and fall off at the end of the growing season
- Spore leaf orientation
- the sporophylls are pressed against the spore cone
- Spore leaf shape
- the spore-bearing leaves are small and scale-like
- Spore leaf teeth
- The edges of the spore-bearing leaves are smooth, and without teeth
- Spore texture
- the spore surface has a net-like pattern on it (reticulate)
- Sterile tip of cone
- there is a slender sterile tip on the end of the spore cone
-
Stem, shoot, branch
- Branch cross-section
- the outermost level of branches are approximately rectangular in cross-section
- Branch form
- the branches are smaller than the main stem
- Constriction zones
-
- there are constricted zones on the horizontal stem where the leaves are smaller smaller or closer together
- there are constricted zones on the vertical stem where the leaves are smaller smaller or closer together
- Form of shoot
- the plant has an upright stem, with branches, those branches having further branches, and so on (tree-like)
- Horizontal stem
- the horizontal stem is on the surface of the ground
- Horizontal stem thickness
- 1.3–2.7 mm
- Stem height
- 150–500 mm
Wetland status
Not classified
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- present
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Massachusetts
- unranked (S-rank: SNR)
From Flora Novae Angliae dichotomous key
2. Diphasiastrum digitatum (Dill. ex A. Braun) Holub N
southern ground-cedar. Diphasium flabelliforme (Fern.) Blanch.; Lycopodium complanatum L. var. flabelliforme Fern.; L. digitatum Dill. ex A. Braun; L. flabelliforme (Fern.) Blanch. • CT, MA, ME, NH, RI, VT; throughout. Upland forests, borders, and fields.
1×2. Diphasiastrum complanatum × Diphasiastrum digitatum → Diphasiastrum ×verecundum A.V. Gilman is a rare ground-cedar hybrid of northern New England ( ME, NH, VT). The upright shoot branches are somewhat irregular (as in D. complanatum), but the stobilus stalk is stouter than in that species and often remains green after sporangium dehiscence. This hybrid may be more common than collections indicate, but the close similarity between its parents makes it difficult to detect.
2×4. Diphasiastrum digitatum × Diphasiastrum tristachyum → Diphasiastrum ×habereri (House) Holub is an infrequent ground-cedar hybrid known from MA, ME, NH, VT. It has winter bud constrictions on the lateral branches, similar to D. tristachyum, but is otherwise intermediate in branch width, relative size of trophophylls of the lower rank, and strobilus stalk branching.
Native to North America?
Yes
Sometimes confused with
- Diphasiastrum tristachyum:
- branches square in cross-section, as wide as 2 mm, with winter bud constrictions, and horizontal shoot buried deeper than 5 cm (vs. D. digitatum, with branches rectangular in cross-section, 2 mm wide or wider, usually without winter bud constrictions, and horizontal shoots at or near the surface).
Synonyms
- Diphasium flabelliforme (Fern.) Blanch.
- Lycopodium complanatum L. var. flabelliforme Fern.
- Lycopodium digitatum Dill. ex A. Braun
- Lycopodium flabelliforme (Fern.) Blanch.