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

Calamagrostis canadensis — bluejoint, Canada reed grass

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New England distribution

Adapted from BONAP data

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North America distribution

Adapted from BONAP data

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Facts

Canada reed grass is found in a variety of habitats in New England. There are three varieties recognized, two of which are regionally rare. The Cree people used this species to line and cover pits that were used to store potatoes in the winter.

Habitat

Alpine or subalpine zones, marshes, meadows and fields, mountain summits and plateaus, shores of rivers or lakes, swamps, wetland margins (edges of wetlands)

Characteristics

Habitat
  • terrestrial
  • wetlands
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont
Leaf blade width
2–11 mm
Inflorescence branches
the flowers are attached to branches rather than to the main axis of the inflorescence
Spikelet length
2–5.2 mm
Glume relative length
one or both glumes are as long or longer than all of the florets
Awn on glume
the glume has no awn
One or more florets
there is one floret per spikelet
Lemma awn length
0.9–3.1 mm
Leaf sheath hair type
there are no hairs on the surface of the leaf sheath
Leaf ligule length
1–12 mm
Anther length
0.8–2.6 mm
Show all characteristics
  • Flowers

    Anther length
    0.8–2.6 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
    1
    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
    • the glume keels are smooth and hairless
    Glume relative length
    one or both glumes are as long or longer than all of the florets
    Glume shape
    • the glume is V-shaped in cross-section
    • the glume is flat or curved 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 length
    2.7–12 cm
    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 spread out, with clearly-evident branches
    Inflorescence length
    60–250 mm
    Inflorescence length to width ratio
    3.1–6
    Inflorescence type (general)
    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
    10–80 mm
    Inforescence position
    the spikelets are mainly carried at the end of the stem
    Lemma awn base
    the awn is attached at the lower half of the lemma (it emerges from near the base of the lemma)
    Lemma awn coiled
    the lemma awn is straight or twisted, but not coiled one half turn
    Lemma awn length
    0.9–3.1 mm
    Lemma awn number
    the lemma has one awn on it
    Lemma awn orientation
    • the awn of the lemma is straight
    • the awn of the lemma on dried or older plants is curved or bent outwards
    Lemma base hair length
    1.5–4.5 mm
    Lemma base hairs
    the lemma has hairs at the base
    Lemma cross-section
    the lemma is flat or rounded if you cut across the midpoint
    Lemma hairs
    the lemma is hairless between the veins
    Lemma surface
    the surface of the lemma is relatively smooth (not counting any longitudinal veins or hairs)
    Lemma tip
    • the lemma tip has a ragged edge
    • the lemma tip is split into two or more points
    Lemma tip shape
    the lemma tip tapers to a long narrow point (it may or may not also have an awn or teeth at the tip)
    Lemma vein number
    5
    Lower glume length
    2.2–6 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 one floret per spikelet
    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 length
    0 mm
    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
    Spikelet length
    2–5.2 mm
    Spikelet number per node
    0
    Spikelet pedicel
    the spikelets have pedicels
    Spikelet position
    the spikelets emerge mainly from the upper halves of the inflorescence branches
    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
    2.2–6 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 at or below the middle
  • Fruits or seeds

    Seed length
    1–1.5 mm
  • Growth form

    Horizontal rooting stem
    no
    Lifespan
    the plant lives more than two years
    Rhizomes
    yes
    Roots
    the plant has rhizomes (horizontal underground stem with roots growing from it)
  • Leaves

    Basal leaves
    the plant has few or no leaves coming from the base of the flowering stem
    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
    10–50 cm
    Leaf blade texture
    the leaf blade is rough and sandpapery
    Leaf blade width
    2–11 mm
    Leaf ligule length
    1–12 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 hair type
    there are no hairs on the surface of the leaf sheath
    Leaf sheath hairs
    there are no hairs on the surface of the leaf sheath
  • Place

    Habitat
    • terrestrial
    • wetlands
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    • Vermont
    Specific habitat
    • alpine or subalpine zones
    • edges of wetlands
    • marshes
    • meadows or fields
    • mountain summits and plateaus
    • shores of rivers or lakes
    • swamps
  • Stem, shoot, branch

    Plant height
    32–180 cm
    Stem hairs
    the stem is nearly to completely hairless
    Stem node number
    2–8
    Stem orientation
    the stems are upright
    Stem spacing
    • the stems grow close together in compact clusters or tufts
    • the stems grow singly or a few together (they may form diffuse colonies)

Wetland status

Occurs only in wetlands. (Wetland indicator code: OBL)

New England distribution and conservation status

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.

Maine
unranked (S-rank: SNR)

var. canadensis

Massachusetts
widespread (S-rank: S5)

var. langsdorfii

New Hampshire
extremely rare (S-rank: S1), endangered (code: E)

var. macouniana

Massachusetts
unranked (S-rank: SNR)
New Hampshire
extremely rare (S-rank: S1), endangered (code: E)
Vermont
historical (S-rank: SH)

var.langsdorfii

Vermont
extremely rare (S-rank: S1)

Native to North America?

Yes

Sometimes confused with

Calamagrostis stricta:
panicle contracted and dense, mostly 10-20 mm wide, lemma with moderately dense callus pubescence usually 50-75% as long as the lemma, and lemma awn antrorsely scabrous throughout its length (vs. C. canadensis, with the panicle loose and open, mostly 20-80 mm wide, lemma with dense callus pubescence mostly 90-120% as long as the lemma, and lemma awn smooth, at least in the basal half).

Synonyms

  • Arundo canadensis Michx.
  • Calamagrostis canadensis var.  robusta (Vasey) Stebbins
  • Deyeuxia canadensis (Michx.) Munro ex Hook. f.

Family

Poaceae

Notes on subspecies and varieties in New England

Calamagrostis canadensis (Michx.) Beauv. var. canadensis is known from CT, MA, ME, NH, RI, VT. C. canadensis var. langsdorfii (Link) Inman is known from NH, VT, is restricted to high elevations, and is of regional conservation concern.C. canadensis var. macouniana (Vasey) Stebbins is known from CT, MA, ME, NH, VT and is of regional conservation concern.

From the dichotomous key of Flora Novae Angliae

1.  Calamagrostis canadensis (Michx.) Beauv. NC

Canada reed grass.  1a. Arundo langsdorfii Link; Calamagrostis canadensis (Michx.) Beauv. var. scabra (J. Presl) A.S. Hitchc.; C. langsdorfii (Link) Trin.; C. nubila Louis-Marie; Deyeuxia langsdorfii (Link) Kunth; D. preslii Kunth;  1b. Arundo canadensis Michx.; Calamagrostis canadensis (Michx.) Beauv. var. robusta (Vasey) Stebbins; Deyeuxia canadensis (Michx.) 
Munro ex Hook. f.;  1c. Calamagrostis macouniana (Vasey) Vasey; Deyeuxia macouniana Vasey • CT, MA, ME, NH, RI, VT; throughout. Wet-mesic to hydric soils of marshes, shorelines, open swamps, and low fields, also in mesic soils of open, boreal to alpine slopes and plateaus, and rarely in mesic to dry-mesic soils.

1a.  Glumes 4–5.2(–6 mm) long, pilose-hirtellous over the abaxial surface, thick and oqaque 
… 1a. C. canadensis var. langsdorfii (Link) Inman

1b.  Glumes 2.2–4(–4.5 mm) long, glabrous or minutely scabrous over the abaxial surface, translucent at least along the margins and at the apex

2a.  Glumes 2.8–4(4.5 mm) long, acute to acuminate at the apex, distinctly longer than 
the lemma … 1b. C. canadensis var. canadensis

2b.  Glumes 2.2–2.8(–3)  mm long, obtuse to acute at the apex, scarcely or not exceeding 
the lemma … 1c. C. canadensis var. macouniana (Vasey) Stebbins

Variety langsdorfii is known from NH, VT; also reported from ME by Knowlton (1899), but specimens are unknown. It is restricted to high elevation areas and is of regional conservation concern. Variety canadensis is known from low to high elevation areas of CT, MA, ME, NH, RI, VT. Variety macouniana is known from CT, MA, ME, NH, VT and is also of regional conservation concern.