Your help is appreciated. We depend on donations to help keep this site free and up to date for you. Can you please help us?

Donate

Native Plant Trust: Go Botany Discover thousands of New England plants

Lobelia dortmanna — water lobelia

Copyright: various copyright holders. To reuse an image, please click it to see who you will need to contact.

Facts

Water lobelia has a circumboreal distribution and is found in shallow waters of lakes and ponds in all New England states. It normally occurs as a submerged rosette of basal leaves with a stem that holds the flowers above water level.

Habitat

Lacustrine (in lakes or ponds), shores of rivers or lakes

New England distribution

Adapted from BONAP data

Found this plant? Take a photo and post a sighting.

North America distribution

Adapted from BONAP data

enlarge

Characteristics

Habitat
  • aquatic
  • wetlands
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont
Flower petal color
  • blue to purple
  • white
Leaf type
the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
Leaf arrangement
  • alternate: there is one leaf per node along the stem
  • basal: the leaves are growing only at the base of the plant
Leaf blade edges
the edge of the leaf blade is entire (has no teeth or lobes)
Flower symmetry
there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)
Number of sepals, petals or tepals
there are five petals, sepals, or tepals in the flower
Fusion of sepals and petals
the petals or the sepals are fused into a cup or tube
Stamen number
5
Fruit type (general)
the fruit is dry and splits open when ripe
Show all characteristics
  • Clonal plantlets

    Bulbils
    the plant does not appear to have bulbils
    Bulblets replace flowers
    there are no bulblets where the flowers are located
  • Flowers

    Anther attachment
    the anther is attached by its base to the filament
    Anther spurs
    the anthers do not have spurs on them
    Calyx growth after flowering
    the calyx grows to cover or partially cover the fruit
    Calyx symmetry
    there is only one way to evenly divide the calyx (the calyx is bilaterally symmetrical)
    Carpels fused
    the carpels are fused to one another
    Cilia on petals
    the petal margins do not have cilia
    Cleistogamous flowers
    there are no cleistogamous flowers on the plan
    Corolla morphology
    the flower has two prominent lips
    Corolla palate
    • no
    • yes
    Corona lobe length
    0 mm
    Epicalyx
    the flower does not have an epicalyx
    Epicalyx number of parts
    0
    Flower appearance
    the flowers appear after the leaves have appeared
    Flower description
    the flower has an inferior ovary, with or without a hypanthium
    Flower length
    12–22 mm
    Flower number
    1–11
    Flower orientation
    • the flower bends downwards or hangs downwards
    • the flower points upwards or is angled outwards
    Flower petal color
    • blue to purple
    • white
    Flower reproductive parts
    the flower has both pollen- and seed-producing parts
    Flower symmetry
    there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)
    Flowers sunken into stem
    no
    Form of style
    the style is lobed at the tip, and unbranched
    Fringed petal edges
    the petals are not fringed
    Fused stamen clusters
    there is one cluster of fused stamens
    Fusion of sepals and petals
    the petals or the sepals are fused into a cup or tube
    Hairs on flower stalk
    the flower stalk has no hairs on it
    Hairs on inflorescence
    the axis of the inflorescence has no hairs on it
    Horns in hoods (Asclepias)
    NA
    Hypanthium
    the flower has a hypanthium
    Inflorescence one-sided
    the flowers are arrayed in a spiral around the inflorescence axis or branches, or occur singly, or in several ranks
    Inner tepals (Rumex)
    NA
    Marks on petals
    there are no noticeable marks on the petals
    Nectar spur
    the flower has no nectar spurs
    Number of branches in umbel
    0
    Number of pistils
    1
    Number of sepals, petals or tepals
    there are five petals, sepals, or tepals in the flower
    Number of styles
    1
    Ovary position
    the ovary is below the point of petal and/or sepal attachment
    Perianth shape
    the perianth is another shape
    Petal and sepal arrangement
    the flower includes two cycles of petal- or sepal-like structures
    Petal and sepal colors
    • blue to purple
    • white
    Petal appearance
    the petals are thin and delicate, and pigmented (colored other than green or brown)
    Petal base
    the petal narrows gradually or does not narrow at the base
    Petal folds or pleats
    the petals of the flower do not have folds or plaits
    Petal glandular dots or scales
    no
    Petal hairs (Viola)
    NA
    Petal hairs on inner/upper surface
    • there are hairs on the inner/upper petal surface
    • there are no hairs on the inner/upper petal surface
    Petal length
    10–20 mm
    Petal length relative to sepals
    the petals are longer than the sepals
    Petal number
    5
    Petal shape
    the petal outline is another shape
    Petal tip shape
    • the petal tip is acute (sharply pointed)
    • the petal tip is obtuse (bluntly pointed)
    Petal tips (Cuscuta)
    NA
    Raceme attachment (Veronica)
    NA
    Reproductive system
    all the flowers have both carpels and stamens (synoecious)
    Scales inside corolla
    no
    Sepal and petal color
    the sepals are different from the petals
    Sepal appearance
    the sepals are green or brown, and leaf-like in texture
    Sepal appendages
    the sepals do not have appendages on them
    Sepal appendages (Oenothera)
    NA
    Sepal auricles
    the sepals have no auricles
    Sepal cilia
    the sepals do not have cilia
    Sepal color
    • blue to purple
    • green to brown
    Sepal number
    5
    Sepal orientation
    • the sepals are pressed against the corolla, or jutting stiffly upward
    • the sepals are slightly curved outwards from the corolla
    Sepal relative length
    the sepal lobes are shorter than the fused portion
    Sepal shape
    • the sepal outline is lanceolate (lance-shaped; narrow, gradually tapering from the base to the tip)
    • the sepal outline is subulate (narrowly tapering from the base to the apex; awl-shaped)
    Sepal tip shape
    • the sepal tip is acute (is sharply pointed)
    • the sepal tip is obtuse (is bluntly pointed)
    Sepal uniformity
    all the sepals are about the same size
    Sepals fused only to sepals
    the sepals are fused to each other (not other flower parts), at least near their bases
    Spur length
    0 mm
    Spur number
    NA
    Stamen attachment
    • the stamens are attached at or near the bases of the petals or tepals
    • the stamens are attached at or near the bases of the petals or tepals
    Stamen morphology
    the stamens within a cycle differ in length or width
    Stamen number
    5
    Stamen position relative to petals
    the stamens are lined up with the sepals
    Stamen relative length
    anything
    Stamens fused
    the stamens are attached to one another at or near their bases
    Staminodes
    there are no staminodes on the flower
    Stigma position
    the stigmas are positioned at the tip of the style
    Style petal-like
    the styles are not petal-like
    Style relative length
    the stigma does not protrude beyond the mouth of the corolla
    Umbel flower reproductive parts
    NA
    Upper lip of bilabiate corolla
    the upper lip of the bilabiate corolla has two lobes
  • Fruits or seeds

    Achene relative orientation
    NA
    Achene shape
    NA
    Achene surface (Polygonum)
    NA
    Achene type
    NA
    Berry color
    NA
    Capsule color (Viola)
    NA
    Capsule ribs
    the capsule has no prominent ribs or wings
    Capsule splitting
    the capsule splits by two main valves, teeth or pores
    Fruit (pyxis) dehiscence
    NA
    Fruit beak length
    0 mm
    Fruit features (Brassicaceae)
    NA
    Fruit length relative to sepals
    • the fruit is about the same length as its associated sepals
    • the fruit is longer than its associated sepals
    Fruit locules
    two
    Fruit shape
    • the fruit is ellipsoid (widest in the middle and tapering to each end)
    • the fruit is obovoid (egg-shaped, but with the widest point above the middle)
    Fruit stalk orientation
    • the fruits curve or droop downwards
    • the fruits point upward or spread or curve outward
    Fruit type (general)
    the fruit is dry and splits open when ripe
    Fruit type (specific)
    the fruit is a capsule (splits along two or more seams, apical teeth or pores when dry, to release two or more seeds)
    Legumes (Fabaceae)
    NA
    Mericarp length
    0 mm
    Mericarp segment shape (Desmodium)
    NA
    Other markings on berry
    NA
    Ovary stipe
    the ovary or fruit does not have a stipe
    Ovary stipe length
    0 mm
    Placenta arrangement
    the plant has axile placentation, in which the ovules are attached where the septa of a compound ovary are united, usually on the central axis, or to the septa themselves
    Rows of seeds in fruit (Brassicaceae)
    NA
    Schizocarpic fruit compression
    NA
    Schizocarpic fruit segments
    0
    Seed length
    0.63–0.81 mm
    Seed relative length
    the seed is longer than it is wide
    Seed surface
    the seed is covered with reticulate markings (a netlike pattern due to splitting and rejoining of lines or ridges)
    Septum in fruit (Brassicaceae)
    NA
    Wings on fruit
    the fruit does not have wings on it
    prickles on fruits
    the fruits do not have thorn-like defensive structures
  • Glands or sap

    Glands on leaf blade
    the leaf blades do not have glandular dots or scales
    Sap
    the sap is milky and opaque, and may be white or colored
    Sap color
    the sap is white
  • Growth form

    Growth form
    the plant is an herb (it has self-supporting stems)
    Horizontal rooting stem
    the plant does not have stolons
    Lifespan
    the plant lives more than two years
    Parasitism
    the plant is not parasitic
    Plant color
    the leaves or young stems of the plant are green
    Plants darken when dry
    no
    Spines on plant
    the plant has no spines
    Underground organs
    there are only slender roots on the plant
  • Leaves

    Bracteole edges
    NA
    Bracteole length
    0 mm
    Bracteole number (Apiaceae)
    0
    Bracteole shape
    the bracteoles are ovate (widest below the middle, and broadly tapering to both ends--egg-shaped)
    Bracteoles
    there are no bracteoles on the plant
    Bracts in plantain (Plantago)
    NA
    Final leaf segment length (compound lvs only)
    0 mm
    Final leaf segment length to width ratio (compound lvs only)
    0
    Final leaf segment width (compound lvs only)
    0 mm
    Floral bracts
    the flower has one or more bracts associated with it
    Flower bract length
    2–3 mm
    Hairs on leaf stalk
    NA
    Hairs on underside of leaf
    the underside of the leaf is not hairy, or it has very few hairs
    Hairs on upper side of leaf
    the upper side of the leaf is not hairy, or it has very few hairs
    Hooked hairs on underside of leaf
    NA
    Inflated hairs on leaf
    the leaf blade does not have inflated hairs on it
    Leaf arrangement
    • alternate: there is one leaf per node along the stem
    • basal: the leaves are growing only at the base of the plant
    Leaf blade base
    the leaf has no stalk
    Leaf blade base symmetry
    the leaf blade base is symmetrical
    Leaf blade bloom
    the underside of the leaf has no noticeable bloom
    Leaf blade edges
    the edge of the leaf blade is entire (has no teeth or lobes)
    Leaf blade hairs
    NA
    Leaf blade length
    Up to 90 mm
    Leaf blade shape
    • the leaf blade is filiform (extremely narrow, thread-like)
    • the leaf blade is linear (very narrow with more or less parallel sides)
    Leaf blade surface colors
    the upper side of the leaf blade is relatively uniform in color
    Leaf blade texture
    • the leaf blade has a fleshy or spongy texture
    • the leaf blade is herbaceous (has a leafy texture)
    Leaf duration
    the leaves drop off in winter (or they whither but persist on the plant)
    Leaf form
    the leaves are green, with an expanded blade and a leaf-like texture
    Leaf hair orientation
    NA
    Leaf sheath length
    0 mm
    Leaf spines
    there are no spines on the leaf edges
    Leaf stalk
    the leaves have no leaf stalks, but attach directly to the stem
    Leaf stalk attachment to leaf
    NA
    Leaf stalk base
    NA
    Leaf stalk length
    0 mm
    Leaf teeth and lobes
    the edge of the leaf blade is entire (has no teeth or lobes)
    Leaf tip
    • the tip of the leaf blade is acute (sharply pointed)
    • the tip of the leaf blade is obtuse (bluntly pointed)
    • the tip of the leaf blade is rounded, with no point
    Leaf tufts in axils
    there are no clusters of smaller leaves growing out of axils
    Leaf type
    the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
    Leaf types
    There is an abrupt change in appearance of the leaves from the base (or near the base) of the plant to those from further up on the stem, with the basal leaves of conspicuously different shape or form than those slightly higher up.
    Leaf variation
    NA
    Leaflet number
    0
    Leaflet petiolules
    NA
    Leaves per node
    • the leaves are growing only at the base of the plant (i.e., basal)
    • there is one leaf per node along the stem
    Pinnately compound leaf type
    NA
    Specific leaf type
    the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
    Stipels
    NA
    Stipule edges
    NA
    Stipule features
    NA
    Stipule fused to leaf stalk
    NA
    Stipule length
    0 mm
    Stipule shape
    NA
    Stipules
    there are no stipules on the plant
    Teeth per side of leaf blade
    At least 0
  • Place

    Habitat
    • aquatic
    • wetlands
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    • Vermont
    Specific habitat
    • in lakes or ponds
    • shores of rivers or lakes
  • Scent

    Plant odor
    the plant does not have much of a smell
  • Stem, shoot, branch

    Branched tendrils
    NA
    Direction of stem hairs
    NA
    Flowering stem cross-section
    the flowering stem is circular, or with lots of small angles so that it is roughly circular
    Hair between stem nodes
    the stem has no hairs between the nodes
    Hairs between stem nodes
    the stem has no hairs between the nodes
    Hooked hairs on stem between nodes
    • NA
    • no
    Leaves on stem
    • the flowering stem has no leaves above the base
    • there is at least one full leaf above the base of the flowering stem
    Length of hairs between stem nodes
    0 mm
    Plant height
    5–100 cm
    Stem hair distribution
    NA
    Stem nodes swollen
    the stem is not swollen at the nodes
    Stem orientation
    the stems are upright or angled outwards
    Stem roughness between nodes
    the stem does not feel rough
    Stem spacing
    the plant is solitary, or a few plants are growing together
    Stem succulence
    • the stems are not succulent
    • the stems are succulent
    Tendril origin
    NA
    Tendrils
    the plant does not have tendrils
    Wings on stem
    the stem does not have wings on it

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.

Massachusetts
fairly widespread (S-rank: S4)
New Hampshire
uncommon (S-rank: S3), W (code: W)
Rhode Island
rare (S-rank: S2), concern (code: C)

From Flora Novae Angliae dichotomous key

2.  Lobelia dortmanna L. N

water lobelia. CT, MA, ME, NH, RI, VT. Shallow water of lakes and ponds. Usually occurring as a submerged rosette of leaves with a stem that elevates the flowers above the water level.

Native to North America?

Yes

Family

Campanulaceae

Genus

Lobelia