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 - 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.