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- Schoenoplectus acutus
Schoenoplectus acutus — hard-stemmed bulrush
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Facts
Some parts of hard-stemmed bulrush were traditionally eaten by several Native American tribes, including the white stem bases, the pith, the young leaf bases, the roots and the seeds. The stems were used in making shoes and clothing, baskets, mats and mattresses, and temporary shelters.
Habitat
Fens (calcium-rich wetlands), 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.
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Characteristics
- 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
- 3–7 mm
- Leaf blade cross-section
- the leaf blade is flat or rolled in at the edges
- Inflorescence position
-
- the inflorescence appears to come from the side of the plant because the involucral bract at its base looks like an extension of the main stem
- the inflorescence is at the tip of the plant
- Inflorescence branching
-
- the inflorescence is branched
- the inflorescence is on one or more stems with no branches
- Fruit type (general)
- the fruit is like a seed, and surrounded by scales
- Fruit length
- 2–2.8 mm
- Leaf position on plant
- the attachment points of all the leaves are at or near the base of the plant
- Perianth composition
- there are bristles attached at the base of the achene
- Fruit cross-section
-
- the fruit is biconvex or elliptic (widest in the middle and tapering to both ends) in cross-section
- the fruit is triangular to terete (circular) in cross-section
-
Flowers
- Anther length
- 1.5–3.5 mm
- Floral bristle color
- the bristles are pale brown to brown
- Floral bristle number
-
- 1-4
- 5-7
- Floral bristle relative length
- the bristles are between one tenth as long as the achene, and equal in length to the achene
- Floral bristles
- the bristles are straight or slightly curved
- Floral scale hairs
- the floral scales have hairs on them
- Floral scale length
- 3–4 mm
- Floral scale shape
- the floral scales are ovate (roughly egg-shaped)
- Floral scale translucent
- the floral scales are translucent
- Flower number per cluster
-
- 5-20
- more than 20
- Inflorescence bract angle
- the bracts are vertical or angled only slightly outwards
- Inflorescence bract number
- there are two to five bracts per 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
- the inflorescence is on one or more stems with no branches
- Inflorescence crowding
- the inflorescence is crowded together in one tight cluster
- Inflorescence position
-
- the inflorescence appears to come from the side of the plant because the involucral bract at its base looks like an extension of the main stem
- 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 are bristles attached at the base of the achene
- Stamen number
- 3
- Stigma number
-
- 2
- 3
- Style division
- the top two thirds of the style is divided
- floral bristle barbs
- the bristles have tiny barbs on them
- plantlets budding at flower bases
- no
-
Fruits or seeds
- Achene beak length
- 0.2–0.5 mm
- 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 biconvex or elliptic (widest in the middle and tapering to both ends) in cross-section
- the fruit is triangular to terete (circular) in cross-section
- Fruit length
- 2–2.8 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 more than two years
- Rhizome thickness
- 5–15 mm
- Underground organs
- the plant has a rhizome (a horizontal underground stem with roots growing from it)
-
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
- 8–120 mm
- Leaf blade width
- 3–7 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
- there are no leaves on the main stem, or there is a small tooth or tiny blade, or a leaf sheath with no blade
-
Place
- Habitat
-
- aquatic
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- fens (calcium-rich wetlands)
- shores of rivers or lakes
-
Stem, shoot, branch
- Plant height
- 100–300 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
- Stem thickness at midpoint
- 1–10 mm
Wetland status
Occurs only in wetlands. (Wetland indicator code: OBL)
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
- rare (S-rank: S2), threatened (code: T)
var. acutus
- Connecticut
- unranked (S-rank: SNR)
- Massachusetts
- rare to uncommon (S-rank: S2S3), #NAME? (code: #NAME?)
From Flora Novae Angliae dichotomous key
1. Schoenoplectus acutus (Muhl. ex Bigelow) A. & D. Löve var. acutus N
hard-stemmed bulrush. Schoenoplectus lacustris (L.) Palla ssp. acutus (Muhl. ex Bigelow) A. & D. Löve; Scirpus acutus Muhl. ex Bigelow; S. occidentalis (S. Wats.) Chase • CT, MA, ME, NH, RI, VT. Shallow water or wet soil of lakes, slow-moving rivers, and fens.
1×5. Schoenoplectus acutus × Schoenoplectus heterochaetus → Schoenoplectus ×oblongus (T. Koyama) Soják is a rare hybrid in New England known from MA, RI, VT. It typically shows a high proportion of solitary spikelets (30–80% of the spikelets are solitary vs. 0–20% in S. acutus). However, the achenes are weakly trigonous in cross-section and commonly have 4 or 5 perianth bristles. Also, each spikelet usually shows a mixture of bifid and trifid styles.
1×10. Schoenoplectus acutus × Schoenoplectus tabernaemontani → This uncommon bulrush hybrid is to be expected anywhere both parents are found growing together. Utilizing only reproductive characters, one can find it difficult to distinguish this hybrid without extreme familiarity with the parental taxa. However, the two species are very different in their vegetative anatomy. The hybrid has 5–8 aerenchymal lacunae in cross-section at ⅔ stem height, each airspace mostly 0.6–1.5 mm in diameter (see identification key for parental character states).
Native to North America?
Yes