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- Avena fatua
Avena fatua — wild oat
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Facts
Wild oat is considered a noxious weed in many parts of the world, having spread from Europe and Central and Southwest Asia to temperate areas worldwide. It was introduced to North America by early European settlers, and is now a common weed of seed crops. It is also frequently found as a contaminant in seed, feed and silage. The twisted lemma awn coils and uncoils in response to changes in humidity and can help corkscrew the seed into the ground.
Habitat
Anthropogenic (man-made or disturbed habitats), meadows and fields
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
- 3–15 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 18–32 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 more than one floret per spikelet
- Lemma awn length
- 23–42 mm
- Leaf ligule length
- 4–6 mm
-
Flowers
- Anther number
- 3
- Awn on glume
- the glume has no awn
- Floret lower bract texture
-
- the lemma is hard and firm
- the lemma is thin and flexible
- Floret number
- 3
- Floret types within spikelet
- all the florets within a spikelet are similar
- Glume awn length
- 0 mm
- Glume relative length
- one or both glumes are as long or longer than all of the florets
- Glume veins
- 7 or more
- Inflorescence arrangement
- the spikelets are uniform
- Inflorescence axis orientation
-
- the inflorescence axis is arched or curved outward
- the inflorescence axis is straight
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Inflorescence length
- 70–400 mm
- Inflorescence length to width ratio
- 1.4–2
- 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
- 50–200 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)
- the awn is attached at the upper half of the lemma
- Lemma awn coiled
- the lemma awn is straight or twisted, but not coiled one half turn
- Lemma awn length
- 23–42 mm
- Lemma awn number
- the lemma has one awn on it
- Lemma awn orientation
- the awn of the lemma on dried or older plants is curved or bent outwards
- Lemma base hair length
- 3.5–5.5 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 has fine hairs between the veins
- Lemma keel hairs
- the keel of the lemma is rough, or has fine hairs
- 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 split into two or more points
- Lemma vein number
-
- 5
- 7 or more
- Lower glume length
- 18–32 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
- 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
- 18–32 mm
- Spikelet pedicel
- the spikelets have pedicels
- Spikelet position
- the spikelets emerge from both the upper and lower halves of the inflorescence branches
- Spikelets spiny
- the spikelets do not appear spiny
- Upper glume length
- 18–32 mm
- Upper glume shape
- the upper glume is widest at or below the middle
-
Fruits or seeds
- Groove on seed
- the caryopsis has a groove running most of its length
-
Growth form
- Lifespan
- the plant lives only a single year or less
-
Leaves
- Leaf auricles
- the leaves do not have auricles
- Leaf basal lobe hairy
- NA
- Leaf blade hairs
- the leaf blade is hairless, but it may have tiny prickles that give it a sand-papery feel
- Leaf blade length
- 10–45 cm
- Leaf blade texture
- the leaf blade is rough and sandpapery
- Leaf blade width
- 3–15 mm
- Leaf ligule length
- 4–6 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 hairs
-
- there are hairs on the surface of the leaf sheath
- there are no hairs on the surface of the leaf sheath
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Vermont
- Specific habitat
-
- man-made or disturbed habitats
- meadows or fields
-
Stem, shoot, branch
- Plant height
- 8–160 cm
- Stem orientation
-
- the stems are upright
- the stems trail at the base, but turn upwards at the tips
- 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
Not classified
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- absent
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Massachusetts
- not applicable (S-rank: SNA)
From Flora Novae Angliae dichotomous key
1. Avena fatua L. E
wild oat. Avena fatua L. var. glabrata Peterm. • CT, MA, ME, NH, VT. Fields, roadsides, disturbed soil.
Native to North America?
No
Sometimes confused with
- Avena sativa:
- lemmas glabrous and spikelets usually with 2 florets (vs. A. fatua, with lemmas pubescent with appressed, brown hairs and spikelets usually with 3 florets).
- Avena strigosa:
- lemmas scabrous near the apex but otherwise without hairs and spikelets usually with 2 florets (vs. A. fatua, with lemmas pubescent with appressed, brown hairs and spikelets usually with 3 florets).
Synonyms
- Avena fatua L. var. glabrata Peterm.