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- Trisetum spicatum
Trisetum spicatum — narrow false oat
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Facts
Narrow false oat is globally one of the most widespread flowering plants, present in arctic and alpine regions of all continents except Africa. It is widespread across northern and western North America, as well as in most New England states. In our region it is found on rivershore outcrops and ledges, and sometimes at higher altitudes, preferring calcareous bedrock.
Habitat
Alpine or subalpine zones, forests, 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
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Vermont
- Leaf blade width
- 1–4 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 5–7.5 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 more than one floret per spikelet
- Lemma awn length
- 3–8 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
- 0.5–4 mm
- Anther length
- 0.6–1.4 mm
-
Flowers
- Anther length
- 0.6–1.4 mm
- Anther number
- 3
- Awn on glume
- the glume has no awn
- 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
- 3
- Inflorescence arrangement
- the spikelets are uniform
- Inflorescence axis orientation
- the inflorescence axis is straight
- 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
- 50–500 mm
- 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
- Inforescence position
- the spikelets are mainly carried at the end of the stem
- Lemma awn base
- the awn is attached at the upper half of the lemma
- Lemma awn length
- 3–8 mm
- Lemma awn number
- the lemma has one awn on it
- Lemma base hairs
- the lemma has hairs at the base
- Lemma cross-section
- the lemma is V-shaped if you cut across the midpoint
- Lemma surface
- the surface of the lemma is relatively smooth (not counting any longitudinal veins or hairs)
- Lemma vein number
-
- 3
- 5
- 7 or more
- One or more florets
- there is more than 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 an extension of the spikelet axis beyond the tip of the spikelet
- Spikelet length
- 5–7.5 mm
- Spikelets spiny
- the spikelets do not appear spiny
- Upper glume shape
- the upper glume is widest at or below the middle
-
Leaves
- Leaf auricles
- the leaves do not have auricles
- Leaf blade width
- 1–4 mm
- Leaf ligule length
- 0.5–4 mm
- Leaf ligule type
- the leaf ligule is in the form of a membrane
- 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 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
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Vermont
- Specific habitat
-
- alpine or subalpine zones
- forests
- ridges or ledges
- shores of rivers or lakes
- woodlands
-
Stem, shoot, branch
- 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
- extremely rare (S-rank: S1), endangered (code: E)
- Maine
- fairly widespread (S-rank: S4)
- Massachusetts
- extremely rare (S-rank: S1), endangered (code: E)
- New Hampshire
- unrankable (S-rank: SU), Ind (code: Ind)
var. molle
- Connecticut
- extremely rare (S-rank: S1)
var. pilosiglume
- Vermont
- extremely rare (uncertain) (S-rank: S1?)
var. spicatum
- Vermont
- uncommon (S-rank: S3)
From Flora Novae Angliae dichotomous key
2. Trisetum spicatum (L.) Richter N
narrow false oat. Aira spicata L.; Trisetum spicatum (L.) Richter var. molle (Kunth) Beal; T. spicatum (L.) Richter var. psilosiglume Fern.; T. triflorum (Bigelow) A. & D. Löve • CT, MA, ME, NH, VT; also reported from RI by Kartesz (1999), but specimens are unknown. River shore outcrops, ledges, often in regions of high-pH bedrock and ascending to subalpine situations.
Native to North America?
Yes
Sometimes confused with
- Corynephorus canescens:
- leaf blades up to 1 mm wide and lemma awn comprised of two distinct and dissimilar parts with a ring of cilia near the middle at the articulation point (vs. T. spicatum, with leaf blades 1-5 mm wide and lemma awns comprised not comprised of two distinct parts and without a ring of cilia near the middle of the awn).
Synonyms
- Aira spicata L.
- Trisetum spicatum (L.) Richter var. molle (Kunth) Beal
- Trisetum spicatum (L.) Richter var. psilosiglume Fern.
- Trisetum triflorum (Bigelow) A. & D. Löve