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- Sagittaria
- Sagittaria cuneata
Sagittaria cuneata — northern arrowhead
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Facts
Northern arrowhead produces three types of leaves, depending on water depth. Strap-shaped phyllodia are found on deep-water plants, floating leaf blades on moderate to deep-water plants, and sagittate leaf blades on recurved petioles on emersed plants. The rhizomes, young leaves, young shoots and young inflorescences are all edible, but it is the corms that are most widely valued for food. The Ojibwa prepared them boiled fresh, dried, or candied them with maple sugar.
Habitat
Floodplain (river or stream floodplains), lacustrine (in lakes or ponds), riverine (in rivers or streams), shores of rivers or lakes, wetland margins (edges of wetlands)
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
- Vermont
- Leaf position
-
- some of the leaves are floating at the surface of the water
- the leaves are all submerged underwater
- Leaf arrangement
- basal: the leaves are growing only at the base of the plant
- Leaf blade length
- 25–450 mm
- Petal or sepal number
- there are three petals, sepals, or tepals in the flower
- Petal color
- white
- Specific leaf type
- the leaf is not divided, rather the blade is made up of one segment
- Floating leaf shape
-
- the leaf blade is cordate (heart-shaped with backward-facing rounded lobes)
- the leaf blade is linear (very narrow with more or less parallel sides)
- the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
- the leaf blade is sagittate (arrow-shaped with backward-facing pointed lobes)
- Fruit type (general)
- the fruit is dry but does not split open when ripe
- Underwater leaf length
- Up to 450 mm
-
Clonal plantlets
- Turion length
- 0 mm
-
Flowers
- Anther color
- there is a noticeable pink, reddish or purplish tint to the anthers
- Carpels fused
- the carpel is solitary or (if 2 or more) the carpels are not fused to one another
- Flower lower lip length
- 0 mm
- Flower number
- 6–30
- Flower position
- the flowers are above the surface of the water
- Flower symmetry
- there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
- Inflorescence length
- 140–210 mm
- Inflorescence type
- the inflorescence is a raceme (a long unbranched stem with stalked flowers growing along it)
- Inflorescence width
- 20–100 mm
- Length of flower stalk
- 5–20 mm
- Length of peduncle
- 100–500 mm
- Nectar spur
- the flower has no nectar spurs
- Number of carpels
- At least 3
- Ovary position
- the sepals and/or petals are attached below the ovary
- Palate on corolla
- no
- Petal and sepal arrangement
- the flower includes two cycles of petal- or sepal-like structures
- Petal appearance
- the petals are thin and delicate, and pigmented (colored other than green or brown)
- Petal color
- white
- Petal fringed edges
- the petals are not fringed
- Petal fusion
- the perianth parts are separate
- Petal hairs on inner/upper surface
- there are no hairs on the inner/upper petal surface
- Petal length
- 7–10 mm
- Petal number
- 3
- Petal or sepal number
- there are three petals, sepals, or tepals in the flower
- Pistil number
-
- 0
- 6 or more
- Sepal appearance
- the sepals resemble leaves in color and texture
- Sepal length
- 4–8 mm
- Sepal number
- 3
- Sepals fused only to sepals
- the sepals are separate from one another
- Spur length
- 0 mm
- Stamen number
-
- 0
- 13 or more
- Stamen position relative to petals
- NA
- Stamens fused
- the stamens are not fused to one another
- Stamens fused to petals
- the stamens are not fused to the petals or tepals
- Style number
- At least 0
-
Fruits or seeds
- Fruit beak length
- 0.1–0.5 mm
- Fruit length
- 1.8–2.6 mm
- Fruit type (general)
- the fruit is dry but does not split open when ripe
- Fruit type (specific)
- the fruit is an achene (dry, usually 1-seeded, does not separate or split open at maturity)
- Fruit width
- 1.3–2.5 mm
-
Glands or sap
- Oil glands on nodes
- none of the nodes have oil glands
- Sap
- the sap is milky and opaque, and may be white or colored
-
Growth form
- Lifespan
- the plant lives more than two years
- Root septa
- the roots have transverse septa
- Roots floating in water
- there are no clusters of roots floating in the water
- Turions
- there are no turions on the plant
- Underground organs
- the plant has one or more swollen storage organs underground, such as bulbs, tubers or corms
-
Leaves
- Bract position (Sparganium)
- NA
- Bract relative length
- At least 1379 mm
- Bracts
- the flowers or their pedicels have bracts at their bases
- Floating leaf basal lobes
- yes
- Floating leaf blade width
- 35–40 mm
- Floating leaf length
- 75–90 mm
- Floating leaf shape
-
- the leaf blade is cordate (heart-shaped with backward-facing rounded lobes)
- the leaf blade is linear (very narrow with more or less parallel sides)
- the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
- the leaf blade is sagittate (arrow-shaped with backward-facing pointed lobes)
- Floating leaf tip
- the tip of the floating leaf blade is acute (sharply pointed)
- Floral bract form
- the bracts are roughly as lobed as the foliage leaves
- Floral bract length
- 4–40 mm
- Leaf arrangement
- basal: the leaves are growing only at the base of the plant
- Leaf blade length
- 25–450 mm
- Leaf blade veins
- the lateral veins are parallel or slightly arched in the direction of the tip
- Leaf blade width
- 15–110 mm
- Leaf position
-
- some of the leaves are floating at the surface of the water
- the leaves are all submerged underwater
- Leaf special features
- none of the mentioned special features are present
- Leaf-like branch segments
- 0
- Leaf-like branch shape
- NA
- Specific leaf type
- the leaf is not divided, rather the blade is made up of one segment
- Staminate bract edge (Myriophyllum)
- NA
- Stipule appearance
- NA
- Stipule fused to leaf
- NA
- Stipules
- there are no stipules on the plant
- Stipules fused around stem
- NA
- Trap-bladder length
- 0 mm
- Underwater leaf air passage number
- At least 1439
- Underwater leaf air passage relative width
- At least 4336
- Underwater leaf air passage row number
- 0
- Underwater leaf blade edges
- the underwater leaf has smooth edges, without teeth
- Underwater leaf blade shape
- the underwater leaf blade is linear (very narrow with more or less parallel sides)
- Underwater leaf length
- Up to 450 mm
- Underwater leaf stalk
- yes
- Underwater leaf stalk length
- Up to 450 mm
- Underwater leaf tip shape
- the tip of the underwater leaf is acute (sharply pointed)
- Veins in floating leaf
- anything
-
Place
- Habitat
-
- aquatic
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Vermont
- Specific habitat
-
- edges of wetlands
- in lakes or ponds
- in rivers or streams
- river or stream floodplains
- shores of rivers or lakes
-
Stem, shoot, branch
- Flowering stem growth form
- the flowering stem is upright
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
- absent
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Connecticut
- extremely rare (S-rank: S1), endangered (code: E)
- Massachusetts
- rare (S-rank: S2), threatened (code: T)
- New Hampshire
- extremely rare (S-rank: S1), endangered (code: E)
From Flora Novae Angliae dichotomous key
1. Sagittaria cuneata Sheldon N
northern arrowhead. Sagittaria arifolia Nutt. ex J.G. Sm. • CT, MA, ME, NH, VT; mainly in northern New England, confined to western half of the southern New England states. Circumneutral to slightly basic water of lakes, slow-moving streams, and pools. Sagittaria cuneata is known to produce three different leaf morphologies—strap-shaped phyllodia on deep-water plants, floating leaf blades on moderate to deep-water plants, and sagittate leaf blades on recurved petioles on emersed plants.
Native to North America?
Yes
Sometimes confused with
- Sagittaria latifolia:
- petals 10-20 mm long, fruit beak 0.6-1.8 mm long and horizontally spreading, and floating leaves never produced (vs. S. cuneata, with petals 7-10 mm long, fruit beak 0.1-0.5 mm long and ascending, and deep water plants producing floating leaves).
Synonyms
- Sagittaria arifolia Nutt. ex J.G. Sm.