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- Bolboschoenus
- Bolboschoenus glaucus
Bolboschoenus glaucus — glaucous tuber-bulrush
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Facts
Glaucous tuber-bulrush, native to Eurasia, was unintentionally introduced to a human-made wetland in New Hampshire, when misidentified rootstock was planted.
Habitat
Marshes, 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
- New Hampshire
- Stem shape in cross-section
- the stem is roughly triangular in cross-section
- Leaf blade width
- 2–6 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
- 2.5–3.3 mm
- Leaf position on plant
-
- some leaf attachment points are above the midpoint of the stem
- 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 color (dry)
- the anthers range in color from white to tan or yellow to yellow-brown
- Anther length
- 3 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
- 5–6 mm
- Floral scale nerves
- 1
- Floral scale shape
-
- the floral scales are ovate (roughly egg-shaped)
- the floral scales are triangular
- Floral scale translucent
- the floral scales are translucent
- Inflorescence bract angle
- the bracts are vertical or angled only slightly outwards
- Inflorescence bract number
-
- there are two to five bracts per inflorescence
- there is just one bract on the inflorescence
- Inflorescence bract position (Sparganium)
- NA
- Inflorescence bracts
- there are at least two bracts, and they are either flat or folded or rolled in at the edges
- 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 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 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
- 2.5–3.3 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
- Underground organs
-
- the plant has a rhizome (a horizontal underground stem with roots growing from it)
- the plant has one or more swollen storage organs underground, such as bulbs or tubers
-
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 width
- 2–6 mm
- Leaf form
- all the leaves hold their form out of water
- Leaf position on plant
-
- some leaf attachment points are above the midpoint of the stem
- 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
- there are no ligules at the leaf blade bases
- Stem leaf blades
- there are fully-developed leaves with leaf blades on the main stem
-
Place
- Habitat
-
- aquatic
- wetlands
- New England state
- New Hampshire
- Specific habitat
-
- marshes
- shores of rivers or lakes
-
Stem, shoot, branch
- Plant height
- 30–150 cm
- Stem shape in cross-section
- the stem is roughly triangular in cross-section
- Stem texture near tip
- the stem feels smooth near the tip
Wetland status
Occurs only in wetlands. (Wetland indicator code: OBL)
In New England
Distribution
- Connecticut
- absent
- Maine
- absent
- Massachusetts
- absent
- New Hampshire
- absent
- Rhode Island
- absent
- Vermont
- absent
Conservation status
None
From Flora Novae Angliae dichotomous key
2. Bolboschoenus glaucus (Lam.) S.G. Smith E
glaucous tuber-bulrush. Schoenoplectus glaucus (Lam.) Kartesz; Scirpus glaucus Lam. • NH. Marshes, shorelines. Unintentionally introduced into a human-made wetland when it was purchased under the name of another tuberous bulrush (i.e., the plant stock was misidentified).
Native to North America?
No
Sometimes confused with
- Bolboschoenus fluviatilis:
- widest leaf blades 7-22 mm wide, spikelets mostly 5-10 mm in diameter, and achenes 3.8-5.5 mm long with an evident style beak 0.1-0.8 mm long (vs. B. glaucus, with the widest leave blades 7-22 mm wide, spikelets mostly 3-5 mm wide, and achenes 2.5-3.3 mm long with a minute style beak).
Synonyms
- Schoenoplectus glaucus (Lam.) Kartesz
- Scirpus glaucus Lam.