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- Sphenopholis obtusata
Sphenopholis obtusata — prairie wedgescale
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Facts
Prairie wedgescale is widely distributed across North America, but in New England it is uncommon to rare, and known only from herbarium specimens in some states, an indicator that it is in decline.
Habitat
Anthropogenic (man-made or disturbed habitats), brackish or salt marshes and flats, marshes, ridges or ledges, shores of rivers or lakes, woodlands
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
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Leaf blade width
- 1–8 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 2.5–3 mm
- Glume relative length
- neither glume is quite as long as all of the florets
- Awn on glume
- the glume has no awn
- One or more florets
- there is more than one floret per spikelet
- Lemma awn length
- 0 mm
- Leaf sheath hair type
-
- there are hairs on the surface of the leaf sheath, but the hairs do not have blisters at their bases
- there are no hairs on the surface of the leaf sheath
- Leaf ligule length
- 1–2.5 mm
- Anther length
- 0.5–0.8 mm
-
Flowers
- Anther length
- 0.5–0.8 mm
- Anther number
- 3
- Awn on glume
- the glume has no awn
- Bristles below spikelets
- no
- Floret lower bract texture
- the lemma is thin and flexible
- Floret number
- 2–3
- Floret types within spikelet
- all the florets within a spikelet are similar
- Glume awn length
- 0 mm
- Glume keel
- the glume keels are rough or hairy
- Glume relative length
- neither glume is quite as long as all of the florets
- Glume shape
- the glume is V-shaped in cross-section
- Glume veins
-
- 1
- 3
- Glumes per spikelet
- 2
- Inflorescence arrangement
- the spikelets are uniform
- Inflorescence axis orientation
-
- the inflorescence axis is arched or curved outward
- the inflorescence axis is straight
- Inflorescence branch roughness
- the inflorescence branches are somewhat to very rough
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Inflorescence crowding
- the panicle is somewhat to very congested (crowded), and the branches may not be clearly seen without close inspection
- Inflorescence length
- 20–250 mm
- Inflorescence length to width ratio
- 4–12.5
- Inflorescence type (general)
-
- the inflorescence is a spike, or is spike-like, lacking obvious branches
- the spikelets are borne on stalks or on branches
- Inflorescence type (specific)
- the inflorescence is branched, and the branches do NOT both grow from the same side of the plant AND look like spikes
- Inflorescence width
- 5–20 mm
- Inforescence position
- the spikelets are mainly carried at the end of the stem
- Lemma awn base
- NA
- Lemma awn coiled
- NA
- Lemma awn length
- 0 mm
- Lemma awn number
- the lemma has no awn
- Lemma awn orientation
- NA
- Lemma base hair length
- 0 mm
- Lemma base hairs
- the lemma is hairless or feels just a tiny bit rough at the base
- Lemma cross-section
- the lemma is V-shaped if you cut across the midpoint
- Lemma hairs
- the lemma is hairless between the veins
- Lemma marginal vein hairs
- the marginal vein of the lemma is hairless
- Lemma surface
- the surface of the lemma is relatively smooth (not counting any longitudinal veins or hairs)
- Lemma tip
- the lemma tip is a simple point, with or without an awn (long narrow extension ending in a point)
- Lemma tip shape
-
- the lemma tip tapers to a broad point (it may or may not also have an awn or teeth at the tip)
- the lemma tip tapers to a narrow point (it may or may not also have an awn or teeth at the tip)
- Lemma vein number
-
- 3
- 5
- Lower glume length
- 1–4 mm
- Lower glume relative length
- the lower glume is nearly as long, or as long as, the upper glume
- One or more florets
- there is more than one floret per spikelet
- Palea length
- 1.8–2 mm
- Palea relative length
- palea is one half to fully as long as lemma
- Reproductive system
- all the flowers on the plant have both carpels and stamens (synoecious)
- Spikelet axis tip
- there is an extension of the spikelet axis beyond the tip of the spikelet
- Spikelet disintegration
-
- the spikelet breaks off above the glumes, so that after the florets fall off, the glumes remain
- the spikelet breaks off below the glumes
- Spikelet length
- 2.5–3 mm
- Spikelet number per node
- Up to 0
- Spikelet pedicel
- the spikelets have pedicels
- Spikelet pedicel length
- 0.2–2 mm
- Spikelet shape
- the spikelets are obovate (egg-shaped but with the widest point above the middle) in profile
- Spikelets spiny
- the spikelets do not appear spiny
- Tip of glume
- the tip of the glume is not divided (though it may have an awn on it)
- Upper glume length
- 1.5–2.5 mm
- Upper glume relative length
- the upper glume is more than one half as long as the lowest lemma
- Upper glume shape
- the upper glume is widest above the middle
-
Growth form
- Horizontal rooting stem
- no
- Lifespan
-
- the plant lives more than two years
- the plant lives only a single year or less
- Rhizomes
- no
- Roots
- there are only slender roots on the plant
-
Leaves
- Leaf auricles
- the leaves do not have auricles
- Leaf basal lobe hairy
- NA
- Leaf blade cross-section
- the leaf blade is more or less flat in cross-section, or slightly folded or rolled inwards
- Leaf blade hairs
-
- the leaf blade is hairless, but it may have tiny prickles that give it a sand-papery feel
- the leaf blade is hairy
- Leaf blade length
- 5–14 cm
- Leaf blade texture
-
- the leaf blade is rough and sandpapery
- the leaf blade is smooth, or it may have soft hairs
- Leaf blade width
- 1–8 mm
- Leaf ligule length
- 1–2.5 mm
- Leaf ligule type
- the leaf ligule is in the form of a membrane
- Leaf margin glands
- there are no glands along the edges of the leaf blade
- Leaf sheath closed around stem
- the margins of the leaf sheath are overlapping and not fused together except in the basal half (or less)
- Leaf sheath color and persistence
- the leaf sheathes are off-white to light-brown and mostly persist in older leaves
- Leaf sheath hair type
-
- there are hairs on the surface of the leaf sheath, but the hairs do not have blisters at their bases
- there are no hairs on the surface of the leaf sheath
- Leaf sheath hairs
-
- there are hairs on the surface of the leaf sheath
- there are no hairs on the surface of the leaf sheath
- Orientation of topmost leaf
- the flag leaf is held upright, or at less than a 45 degree angle out from the stem
-
Place
- Habitat
-
- terrestrial
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- brackish or salt marshes and flats
- man-made or disturbed habitats
- marshes
- ridges or ledges
- shores of rivers or lakes
- woodlands
-
Stem, shoot, branch
- Hairs at nodes
- the stem nodes are hairless or they have very sparse hairs
- Plant height
- 9–130 cm
- Roots at lower stem nodes
- no
- Stem orientation
- the stems are upright
- Stem spacing
- the stems grow close together in compact clusters or tufts
Wetland status
Occurs in wetlands or non-wetlands. (Wetland indicator code: FAC)
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.
- Connecticut
- unrankable (S-rank: SU)
- Maine
- historical (S-rank: SH), potentially extirpated (code: PE)
- Massachusetts
- historical (S-rank: SH), H (code: H)
- New Hampshire
- historical (S-rank: SH), endangered (code: E)
- Rhode Island
- extremely rare (S-rank: S1), concern (uncertain) (code: C*)
- Vermont
- extremely rare (S-rank: S1), endangered (code: E)
From Flora Novae Angliae dichotomous key
3. Sphenopholis obtusata (Michx.) Scribn. NC
prairie wedgescale. Eatonia obtusata Gray; Sphenopholis obtusata (Michx.) Scribn. var. lobata (Trin.) Scribn. • CT, MA, ME, NH, RI, VT. Upper edges and drier portions of saline and brackish marshes, woodlands, ledges, river and lake shores, roadsides.
Native to North America?
Yes
Sometimes confused with
- Sphenopholis intermedia:
- upper glume acute at the apex, spikelets 3–4.2 mm long, and anthers 0.3–0.5 mm long (vs. S. obtusata, with upper glume broad-rounded to truncate at the apex, spikelets 2.5–3 mm long, and anthers 0.5–0.8 mm).
- Sphenopholis nitida:
- second lemma prominently scabrous and anthers 1.2–1.6 mm long (vs. S. obtusata, with second lemma smooth to minutely scabrous and anthers 0.5–0.8 mm long).
Synonyms
- Eatonia obtusata Gray
- Sphenopholis obtusata (Michx.) Scribn. var. lobata (Trin.) Scribn.