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

Polanisia dodecandra — red-whiskered clammyweed

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

Facts

Red-whiskered clammyweed is a distinctive plant, of which there are two subspecies in New England. Although both are widely distributed in North America, they have spread along roads and railroads into new areas. One subspecies (Polanisia dodecandra ssp. dodecandra) is native to Connecticut and Vermont, and introduced to Massachusetts and New Hampshire. The other (P. dodecandra ssp. trachysperma) is more common in western North America, and is introduced to New England. The former subspecies has smaller flowers and stamens barely longer than the petals, while the latter has larger flowers and stamens much longer than the petals.

Habitat

Anthropogenic (man-made or disturbed habitats), 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
  • terrestrial
  • wetlands
New England state
  • Connecticut
  • Massachusetts
  • New Hampshire
  • Vermont
Flower petal color
  • blue to purple
  • pink to red
  • white
Leaf type
the leaves are compound (made up of two or more discrete leaflets
Leaf arrangement
alternate: there is one leaf per node along the stem
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 four petals, sepals, or tepals in the flower
Fusion of sepals and petals
both the petals and sepals are separate and not fused
Stamen number
  • 10
  • 11
  • 12
  • 13 or more
Fruit type (general)
the fruit is dry and splits open when ripe
Fruit length
40–70 mm
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 opening
    the anthers have narrow slits or furrows that run lengthwise along the anthers
    Anther spurs
    the anthers do not have spurs on them
    Calyx symmetry
    there are two or more ways to evenly divide the calyx (the calyx is radially symmetrical)
    Carpels fused
    the carpels are fused to one another
    Cleistogamous flowers
    there are no cleistogamous flowers on the plan
    Corolla palate
    no
    Corona lobe length
    0 mm
    Epicalyx
    the flower does not have an epicalyx
    Epicalyx number of parts
    0
    Flower description
    the flower has a superior ovary, and lacks a hypanthium
    Flower petal color
    • blue to purple
    • pink to red
    • white
    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 knob-like at the tip, and unbranched
    Fusion of sepals and petals
    both the petals and sepals are separate and not fused
    Horns in hoods (Asclepias)
    NA
    Hypanthium
    the flower does not have 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
    Nectar spur
    the flower has no nectar spurs
    Number of pistils
    1
    Number of sepals, petals or tepals
    there are four petals, sepals, or tepals in the flower
    Ovary position
    the ovary is above the point of petal and/or sepal attachment
    Petal and sepal arrangement
    the flower includes two cycles of petal- or sepal-like structures
    Petal and sepal colors
    • blue to purple
    • pink to red
    • white
    Petal appearance
    the petals are thin and delicate, and pigmented (colored other than green or brown)
    Petal folds or pleats
    the petals of the flower do not have folds or plaits
    Petal hairs (Viola)
    NA
    Petal number
    4
    Petal tips (Cuscuta)
    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 appendages
    the sepals do not have appendages on them
    Sepal appendages (Oenothera)
    NA
    Stamen attachment
    the stamens are not attached to the petals or tepals
    Stamen number
    • 10
    • 11
    • 12
    • 13 or more
    Stamen position relative to petals
    NA
    Staminodes
    there are no staminodes on the flower
    Umbel flower reproductive parts
    NA
    Upper lip of bilabiate corolla
    NA

  • 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 splitting
    • NA
    • the capsule splits by two main valves, teeth or pores
    Fruit (pyxis) dehiscence
    NA
    Fruit features (Brassicaceae)
    NA
    Fruit length
    40–70 mm
    Fruit locules
    two
    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
    Rows of seeds in fruit (Brassicaceae)
    NA
    Schizocarpic fruit compression
    NA
    Schizocarpic fruit segments
    0
    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

    Sap
    the sap is clear and watery
    Sap color
    the sap is clear

  • Growth form

    Horizontal rooting stem
    the plant does not have stolons
    Lifespan
    • the plant lives more than two years
    • the plant lives only a single year or less
    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

  • Leaves

    Bracteole number (Apiaceae)
    0
    Bracts in plantain (Plantago)
    NA
    Hairs on underside of leaf
    the underside of the leaf is fuzzy or hairy
    Leaf arrangement
    alternate: there is one leaf per node along the stem
    Leaf blade base
    the leaf has a distinct leaf stalk (petiole)
    Leaf blade base shape
    • the base of the leaf blade is cordate (heart-shaped, has rounded lobes at the base)
    • the base of the leaf blade is rounded
    Leaf blade edges
    the edge of the leaf blade is entire (has no teeth or lobes)
    Leaf blade shape
    • the leaf blade is elliptic (widest near the middle and tapering at both ends)
    • the leaf blade is oblanceolate (lance-shaped, but with the widest point above the middle of the leaf blade)
    • the leaf blade is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
    Leaf blade surface colors
    the upper side of the leaf blade is relatively uniform in color
    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 spines
    there are no spines on the leaf edges
    Leaf teeth and lobes
    the edge of the leaf blade is entire (has no teeth or lobes)
    Leaf type
    the leaves are compound (made up of two or more discrete leaflets
    Leaves per node
    there is one leaf per node along the stem
    Specific leaf type
    • the leaf has a row of two or more lobes on each side of the central axis
    • the leaf has lobes that radiate from the base, somewhat like a hand
    Stipule features
    NA
    Stipules
    there are no stipules on the plant

  • Place

    Habitat
    • terrestrial
    • wetlands
    New England state
    • Connecticut
    • Massachusetts
    • New Hampshire
    • Vermont
    Specific habitat
    • man-made or disturbed habitats
    • shores of rivers or lakes

  • Stem, shoot, branch

    Branched tendrils
    NA
    Hairs between stem nodes
    at least some of the hairs on the stem have glands
    Hooked hairs on stem between nodes
    no
    Leaves on stem
    there is at least one full leaf above the base of the flowering stem
    Plant height
    At least 5 cm
    Tendril origin
    NA
    Tendrils
    the plant does not have tendrils

Wetland status

Occurs only in non-wetlands. (Wetland indicator code: UPL)

In New England

Distribution

Connecticut
present
Maine
absent
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
historical (S-rank: SH), special concern, extirpated (code: SC*)

ssp. dodecandra

Massachusetts
not applicable (S-rank: SNA)

ssp. trachysperma

Massachusetts
not applicable (S-rank: SNA)

Subspecies and varieties

Subspecies dodecandra is known from CT, MA, NH, VT. It is native to CT and VT and introduced in MA and NH. Subspecies trachysperma is known from CT, MA. It is non-native to New England.

From Flora Novae Angliae dichotomous key

1.  Polanisia dodecandra (L.) DC. N│E

red-whiskered clammyweed. 1a. Polanisia graveolens Raf.; 1b. Polanisia dodecandra (L.) DC. var. trachysperma (Torr. & Gray) Iltis; P. trachysperma Torr. & Gray • CT, MA, NH, VT; also reported from ME by Tucker (2010), but specimens are unknown. Sandy and stony lake shores, dry banks, railroads.

1a.  Petals 3.5–6.5 (–8) mm long; longest stamens 4–10 (–14) mm long, scarcely if at all exceeding the petals … 1a. P. dodecandra ssp. dodecandra

1b.  Petals (7–) 8–13 (–16) mm long; longest stamens (9–) 12–30 mm long, much exceeding the petals … 1b. P. dodecandra ssp. trachysperma (Torr. & Gray) Iltis

Subspecies dodecandra is known from CT, MA, NH, VT. It is native to CT and VT and introduced in MA and NH. Subspecies trachysperma is known from CT, MA. It is non-native to New England.

Native to North America?

Yes and no (some introduced)

Sometimes confused with

Peritoma serrulata:
petals retuse at the apex or sometimes merely truncate, flowers with mostly 10–27 stamens, and fruit elevated on a gynophore mostly 0–2 mm long (vs. P. serrulata, with the petals entire at the apex, flowers with 6 stamens, and fruit elevated on a gynophore mostly 1–80 mm long).
Tarenaya hassleriana:
leaves with 5 or 7 leaflets, petals entire at apex, and flowers with 6 stamens (vs. P. dodecandra, with leaves with 3 leaflets, petals retuse at the apex, and flowers with 7-27 stamens).

Synonyms

  • Polanisia graveolens Raf.

Family

Cleomaceae

Genus

Polanisia