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Native Plant Trust: Go Botany Discover thousands of New England plants

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

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North America distribution

Adapted from BONAP data

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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
Show all characteristics
  • 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.

Family

Poaceae

Genus

Sphenopholis