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- Poaceae
- Poaceae Group 7
- Piptatherum
- Piptatherum canadense
Piptatherum canadense — Canada mountain-rice grass
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Facts
Canada mountain-rice grass has a wide distribution across Canada, extending southwards into northern New England. Although uncommon throughout its range, it is especially so in New England, where it is confined to a few populations in Maine and New Hampshire. It inhabits open areas in dry (or occasionally moist), sandy or very rocky, nutrient-poor soils. This species depends on disturbances that open the canopy and create bare soil conditions (such as fire or rock slides). Changes in natural disturbance regimes are the biggest threats to Canada mountain-rice grass in New England.
Habitat
Cliffs, balds, or ledges, forests, meadows and fields, ridges or ledges, shrublands or thickets, talus and rocky slopes, 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.
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Characteristics
- Habitat
- terrestrial
- New England state
-
- Maine
- New Hampshire
- Leaf blade width
- 0.5–2 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 3–6 mm
- Glume relative length
-
- neither glume is quite as long as all of the florets
- 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
- 6–11 mm
- Leaf sheath hair type
- there are no hairs on the surface of the leaf sheath
- Leaf ligule length
- 1–4 mm
- Anther length
- 1–2 mm
-
Flowers
- Anther length
- 1–2 mm
- Anther number
- 3
- Awn on glume
- the glume has no awn
- Bristles below spikelets
- no
- Floret lower bract texture
- the lemma is hard and firm
- Floret number
- 1
- Floret types within spikelet
- all the florets within a spikelet are similar
- Glume awn length
- 0 mm
- Glume relative length
-
- neither glume is quite as long as all of the florets
- one or both glumes are as long or longer than all of the florets
- 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
- 1–6 cm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Inflorescence branches coming off the lowest stem node
- 1–2
- Inflorescence crowding
- the panicle is somewhat to very spread out, with clearly-evident branches
- Inflorescence length
- 90–150 mm
- 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
- Inforescence position
- the spikelets are mainly carried at the end of the stem
- Lemma awn base
- the awn is attached right at the tip of the lemma
- Lemma awn coiled
-
- the lemma awn is coiled at least one half turn
- the lemma awn is straight or twisted, but not coiled one half turn
- Lemma awn length
- 6–11 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 hairs
- the lemma has hairs at the base
- Lemma base length
- 0.1–0.5 mm
- Lemma cross-section
- the lemma is flat or rounded if you cut across the midpoint
- Lemma hairs
- the lemma has fine hairs between the veins
- Lemma keel hairs
- NA
- Lemma marginal vein hairs
- the marginal vein of the lemma has fine hairs on it
- 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 narrow point (it may or may not also have an awn or teeth at the tip)
- Lemma vein number
-
- 3
- 5
- 7 or more
- Lower glume length
- 3–6 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 tip
- there is no 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
- 3–6 mm
- Spikelet number per node
- Up to 0
- Spikelet pedicel
- the spikelets have pedicels
- Spikelet position
- the spikelets emerge mainly from the upper halves of the inflorescence branches
- Spikelet shape
-
- the spikelets are elliptic (widest in the middle, tapering to the ends) in profile
- the spikelets are lanceolate (lance-shaped, widest below the middle and tapering narrowly to the ends) 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
- 3–6 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 above the middle
- the upper glume is widest at or below the middle
-
Growth form
- Lifespan
- the plant lives more than two years
- Rhizomes
- no
- Roots
- there are only slender roots on the plant
-
Leaves
- Basal leaves
- the plant has large or prominent tufts of leaves at 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 clearly folded or rolled inwards
- the leaf blade is more or less flat in cross-section, or slightly folded or rolled inwards
- Leaf blade length
- 1–15 cm
- Leaf blade width
- 0.5–2 mm
- Leaf ligule length
- 1–4 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
- 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
- New England state
-
- Maine
- New Hampshire
- Specific habitat
-
- cliffs, balds, or ledges
- forests
- meadows or fields
- ridges or ledges
- shrublands or thickets
- talus or rocky slopes
- woodlands
-
Stem, shoot, branch
- Hairs at nodes
- the stem nodes are hairless or they have very sparse hairs
- Plant height
- 30–90 cm
- Roots at lower stem nodes
- no
- Stem hairs
- the stem is nearly to completely hairless
- Stem node number
- 1–6
- Stem orientation
- the stems are upright
- Stem spacing
- the stems grow close together in compact clusters or tufts
Wetland status
Not classified
In New England
Distribution
- Connecticut
- absent
- Maine
- present
- Massachusetts
- absent
- New Hampshire
- present
- Rhode Island
- absent
- Vermont
- absent
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Maine
- rare (S-rank: S2), special concern (code: SC)
- New Hampshire
- extremely rare (S-rank: S1), endangered (code: E)
From Flora Novae Angliae dichotomous key
1. Piptatherum canadense (Poir.) Dorn NC
Canada mountain-rice grass. Oryzopsis canadensis (Poir.) Torr.; Stipa canadensis Poir. • ME, NH. Dry-mesic forests, woodlands, fields, and heath barrens, rock outcrops and balds, talus slopes.
Native to North America?
Yes
Sometimes confused with
- Piptatherum pungens:
- awn of lemma 0.5–2 mm long or rarely absent, straight or slightly bent, and glumes minutely scabrous in the apical portion (vs. P. canadense, with the awn of lemma 6–11 mm long, often bent or twisted in the basal half, and glumes glabrous).
Synonyms
- Oryzopsis canadensis (Poir.) Torr.
- Stipa canadensis Poir.