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- Dichotomous Key
- Poaceae
- Poaceae Group 7
- Apera
- Apera spica-venti
Apera spica-venti — loose silky bentgrass
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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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Facts
Loose silky bentgrass was introduced to North America from Europe, probably as a contaminant of imported seed grain, as early as 1800. It continues to be a major weed of winter wheat in Europe. In the Northeast, it is mainly a weed of lawns, roadsides, fields and disturbed, sandy sites. Like dense silky bentgrass (Apera interrupta) it germinates in the fall, overwinters as a seedling, and flowers in the spring.
Habitat
Anthropogenic (man-made or disturbed habitats), meadows and fields
Characteristics
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- Vermont
- Leaf blade width
- 3–5 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 2.4–3.2 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
- 5–12 mm
- Leaf ligule length
- 3–12 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 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
- Glume relative length
- 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 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
- 50–350 mm
- Inflorescence length to width ratio
- 2.3–2.5
- 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
- 20–150 mm
- 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 coiled
- the lemma awn is straight or twisted, but not coiled one half turn
- Lemma awn length
- 5–12 mm
- Lemma awn number
- the lemma has one awn on it
- Lemma awn orientation
- the awn of the lemma is straight
- 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 keel hairs
- the keel of the lemma is rough, or has fine hairs
- 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
- Lower glume length
- 1.5–2.5 mm
- Lower glume relative length
- the lower glume is one third to three quarters 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 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
- 2.4–3.2 mm
- Spikelet number per node
- 0
- Spikelet pedicel
- the spikelets have pedicels
- Spikelet pedicel length
- 1–3 mm
- 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
- 2.4–3.2 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 only a single year or less
- Rhizomes
- no
- Roots
- there are only slender roots on the plant
-
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
- Leaf blade length
- 6–25 cm
- Leaf blade width
- 3–5 mm
- Leaf ligule length
- 3–12 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 color and persistence
- the leaf sheathes are reddish-brown and disintegrate or become shredded in older leaves
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- Vermont
- Specific habitat
-
- man-made or disturbed habitats
- meadows or fields
-
Stem, shoot, branch
- Plant height
- 20–120 cm
- Stem hairs
- the stem is nearly to completely hairless
Wetland status
Not classified
New England distribution and conservation status
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- absent
- 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)
Native to North America?
No
Sometimes confused with
- Agrostis elliottiana:
- flowers lacking or with minute paleas and with 1 anther 0.1-0.2 mm long (vs. A. spica-venti, with flowers with well developed paleas 3/4 to fully as long as the associated lemma and with 3 anthers 1-2 mm long
- Apera interrupta:
- leaf blades mostly 1-3 mm wide, panicles contracted and 4-30 mm wide, and anthers 0.3-0.5 mm long (vs. A. spica-venti, with leaf blades mostly 2-5 mm wide, panicles relatively open and 20-150 mm wide, and anthers 1-2 mm long).
Synonyms
- Agrostis spica- venti L.
Family
Genus
From the dichotomous key of Flora Novae Angliae
2. Apera spica-venti (L.) Beauv. E
loose silky bentgrass. Agrostis spica- venti L. • CT, MA, ME, VT. Lawns, roadsides, fields, disturbed sandy places.