Fimbristylis autumnalis — slender fimbry
![Stems and sheaths: Fimbristylis autumnalis. ~ By Troy University Herbarium. ~ Copyright © 2024. ~ Brian Keener, bkeener[at]uwa.edu ~ Troy U. Herbarium](https://newfs.s3.amazonaws.com/taxon-images-1000s1000/Cyperaceae/fimbristylis-autumnalis-ss-troyherb1.jpg)
![Inflorescences: Fimbristylis autumnalis. ~ By Arthur Haines. ~ Copyright © 2024 Arthur Haines. ~ arthur.d.haines[at]gmail.com](https://newfs.s3.amazonaws.com/taxon-images-1000s1000/Cyperaceae/fimbristylis-autumnalis-in-ahaines.jpg)
![Leaves and auricles: Fimbristylis autumnalis. ~ By John Bradford and George Rogers. ~ Copyright © 2024 John Bradford and George Rogers. ~ George Rogers: rogersg[at]palmbeachstate.edu, 561-207-5052 ~ floridagrasses.org/index.htm](https://newfs.s3.amazonaws.com/taxon-images-1000s1000/Cyperaceae/fimbristylis-autumnalis-la-flgrasses1.jpg)
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Facts
Slender fimbry is a native plant that grows in sandy or peaty pond shores, temporarily wet sites, and sometimes in areas of human disturbance. Although it is found in all New England states and much of eastern North America, it is listed as rare in Maine and Vermont. This graceful member of the sedge family gets its common name from its slender stems, which are topped by delicate spikes borne on long bracnhes.
Habitat
Anthropogenic (man-made or disturbed habitats), lacustrine (in lakes or ponds), shores of rivers or lakes
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.
enlargeCharacteristics
- Habitat
-
- aquatic
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Stem shape in cross-section
- the stem is round or oval in cross-section
- Leaf blade width
- 1–3 mm
- Leaf blade cross-section
- the leaf blade is flat or rolled in at the edges
- Inflorescence position
- the inflorescence is at the tip of the plant
- Inflorescence branching
- the inflorescence is branched
- Fruit type (general)
- the fruit is like a seed, and surrounded by scales
- Fruit length
- 0.5–0.7 mm
- Leaf position on plant
- the attachment points of all the leaves are at or near the base of the plant
- Perianth composition
- there is no perianth on the plant
- Fruit cross-section
- the fruit is triangular to terete (circular) in cross-section
-
Flowers
- Floral bristle color
- NA
- Floral bristle number
- 0
- Floral bristle relative length
- NA
- Floral bristles
- NA
- Floral scale hairs
- there are no hairs on the floral scales
- Floral scale length
- 1.5–2 mm
- Floral scale shape
- the floral scales are lanceolate (widest below the middle, and tapering at both ends)
- Floral scale translucent
- the floral scales are opaque
- Flower number per cluster
-
- 1
- 2-5
- 5-20
- more than 20
- Inflorescence bract angle
- the bracts are angled outwards near horizontal or reflexed downwards
- Inflorescence bract number
- there is just one bract on the inflorescence
- Inflorescence bract position (Sparganium)
- NA
- Inflorescence bracts
- there is only one bract, and it looks like a continuation of the stem
- Inflorescence branching
- the inflorescence is branched
- Inflorescence crowding
- the inflorescence is at least somewhat spread out, with at least one branch coming from the main stem
- Inflorescence position
- the inflorescence is at the tip of the plant
- Inflorescence shape
- the aggregations within the inflorescence are roughly circular (not flattened) in cross-section
- Inflorescence type
- there are two or more flowers, spikes or flower clusters on a branched inflorescence
- Perianth composition
- there is no perianth on the plant
- Stamen number
-
- 1
- 2
- Stigma number
- 3
- Style division
- the top two thirds of the style is divided
- floral bristle barbs
- NA
- plantlets budding at flower bases
- no
-
Fruits or seeds
- Achene surface texture
- the achene is smooth (it has no detectable texture)
- Achene tubercle relative width
- NA
- Achene tubercle width
- 0 mm
- Capsule relative length
- NA
- Fruit cross-section
- the fruit is triangular to terete (circular) in cross-section
- Fruit length
- 0.5–0.7 mm
- Fruit type (general)
- the fruit is like a seed, and surrounded by scales
- Fruit type (specific)
- the fruit is an achene (dry, seed-like fruit) without a tubercle (a swelling or projection, usually of a different color or texture)
- Locules in capsule
- NA
- Seed length
- 0 mm
- Seed tail relative length
- 0 mm
- Seed tails
- NA
- Tubercle height
- 0 mm
-
Growth form
- Lifespan
- the plant lives only a single year or less
- Underground organs
- there are only slender roots on the plant
-
Leaves
- Auricle length
- 0 mm
- Auricle texture
- NA
- Auricles
- there are no auricles on the leaf sheath
- Leaf blade cross-section
- the leaf blade is flat or rolled in at the edges
- Leaf blade length
- Up to 150 mm
- Leaf blade width
- 1–3 mm
- Leaf form
- all the leaves hold their form out of water
- Leaf position on plant
- the attachment points of all the leaves are at or near the base of the plant
- Leaf septa
- the leaf blades do not have transverse septa
- Leaf sheath hairs
- the leaf sheathes are without hairs
- Pedicel length (Typha)
- 0 mm
- Stem leaf blade ligules
- the plant has ligules at the leaf blade bases
- Stem leaf blades
- there are fully-developed leaves with leaf blades on the main stem
- Width of seed-producing inflorescence
- 1–1.5 mm
-
Place
- Habitat
-
- aquatic
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- in lakes or ponds
- man-made or disturbed habitats
- shores of rivers or lakes
-
Stem, shoot, branch
- Plant height
- 5–30 cm
- Stem shape in cross-section
- the stem is round or oval in cross-section
- Stem texture near tip
- the stem feels smooth near the tip
Wetland status
Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)
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.
- Maine
- rare to uncommon (S-rank: S2S3), threatened (code: T)
- Massachusetts
- unranked (S-rank: SNR)
- Vermont
- extremely rare (S-rank: S1), endangered (code: E)
From Flora Novae Angliae dichotomous key
1. Fimbristylis autumnalis (L.) Roemer & J.A. Schultes N
slender fimbry. Fimbristylis autumnalis (L.) Roemer & J.A. Schultes var. mucronulata (Michx.) Fern.; Scirpus autumnalis L. • CT, MA, ME, NH, RI, VT. Sandy or peaty pond shores, pools, and temporary wet areas, sometimes occurring in human-disturbed habitats.
Native to North America?
Yes
Sometimes confused with
Synonyms
- Fimbristylis autumnalis (L.) Roemer & J.A. Schultes var. mucronulata (Michx.) Fern.
- Scirpus autumnalis L.