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

Caulophyllum giganteum — early blue cohosh

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Facts

Early blue cohosh is an endemic of the northeastern and east-central North America, and flowers ten to fifteen days earlier than its close relative blue cohosh (Caulophyllum thalictoides). The two species can also be distinguished on vegetative characters. Early blue cohosh inhabits moist deciduous forests, usually on rich, rocky soils.

Habitat

Floodplain (river or stream floodplains), forests

New England distribution

Adapted from BONAP data

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North America distribution

Adapted from BONAP data

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Characteristics

Habitat
terrestrial
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont
Flower petal color
  • blue to purple
  • green to brown
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 has lobes, or it has both teeth and lobes
  • the edge of the leaf blade is entire (has no teeth or lobes)
Flower symmetry
there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
Number of sepals, petals or tepals
there are six petals, sepals, or tepals in the flower
Fusion of sepals and petals
both the petals and sepals are separate and not fused
Stamen number
6
Fruit type (general)
  • NA
  • the fruit is dry but does not split open when ripe
Fruit length
5–8 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 flaps on them that cover the opening
    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 carpel is solitary or (if 2 or more) the carpels are not fused to one another
    Cleistogamous flowers
    there are no cleistogamous flowers on the plan
    Corolla morphology
    NA
    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
    • green to brown
    Flower symmetry
    there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
    Flowers sunken into stem
    no
    Form of style
    NA
    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 six 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
    • green to brown
    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
    6
    Petal tip shape
    the petal tip is rounded
    Petal tips (Cuscuta)
    NA
    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
    Sepal number
    6
    Stamen attachment
    • the stamens are not attached to the petals or tepals
    • the stamens are not attached to the petals or tepals
    Stamen number
    6
    Stamen position relative to petals
    the stamens are lined up with the petals
    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 ribs
    NA
    Capsule splitting
    NA
    Fruit (pyxis) dehiscence
    NA
    Fruit beak length
    0 mm
    Fruit cross-section
    • NA
    • the fruit is round in cross-section
    Fruit features (Brassicaceae)
    NA
    Fruit length
    5–8 mm
    Fruit locules
    NA
    Fruit type (general)
    • NA
    • the fruit is dry but does not split open when ripe
    Fruit type (specific)
    • NA
    • the fruit is a drupe (fleshy, with a firm inner ovary wall that encloses a single seed)
    Legumes (Fabaceae)
    NA
    Mericarp segment shape (Desmodium)
    NA
    Other markings on berry
    NA
    Ovary stipe
    the ovary or fruit does not have a stipe
    Placenta arrangement
    the plant has basal placentation, where one or a few ovules develop at the base of a simple or compound ovary
    Rows of seeds in fruit (Brassicaceae)
    NA
    Schizocarpic fruit compression
    NA
    Schizocarpic fruit segments
    0
    Septum in fruit (Brassicaceae)
    NA
    Wings on fruit
    • NA
    • 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 clear and watery
    Sap color
    the sap is clear

  • Growth form

    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

  • Leaves

    Bracteole number (Apiaceae)
    0
    Bracts in plantain (Plantago)
    NA
    Final leaf segment length (compound lvs only)
    50–100 mm
    Hairs on underside of leaf
    the underside of the leaf is not hairy, or it has very few hairs
    Leaf arrangement
    alternate: there is one leaf per node along the stem
    Leaf blade edges
    • the edge of the leaf blade has lobes, or it has both teeth and lobes
    • the edge of the leaf blade is entire (has no teeth or lobes)
    Leaf blade surface colors
    the upper side of the leaf blade is relatively uniform in color
    Leaf blade vein pattern
    the major veins of the leaf blade branch, but do not rejoin
    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 stalk attachment to leaf
    the petiole attaches at the basal margin of the leaf blade
    Leaf stalk base
    the petiole base is narrow where it attaches to the stem
    Leaf teeth and lobes
    • the edge of the leaf blade is entire (has no teeth or lobes)
    • the leaf has a row of two or more lobes on each side of the central axis
    Leaf type
    the leaves are compound (made up of two or more discrete leaflets
    Leaf types
    • NA
    • There is a gradual 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 leaves progressively changing as one moves higher on the stem (often becoming shorter, or less toothed/lobed, and/or with shorter petioles).
    Leaf variation
    the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem
    Leaflet petiolules
    the leaflets of the compound leaf have petiolules
    Leaves per node
    there is one leaf per node along the stem
    Pinnately compound leaf type
    the pinnately compound leaves have a terminal leaflet (and usually have an odd number of leaflets per axis)
    Specific leaf type
    • the leaf has a row of two or more lobes on each side of the central axis, and each lobe itself has rows of lobes on each side of the lobe's central axis
    • the leaf has lobes that themselves have lobes, and these secondary lobes also have lobes; there may be more than three levels of lobes
    Stipels
    there are no stipels at the bases of the petiolules
    Stipule features
    NA
    Stipules
    there are no stipules on the plant

  • Place

    Habitat
    terrestrial
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    • Vermont
    Specific habitat
    • forests
    • river or stream floodplains

  • Stem, shoot, branch

    Branched tendrils
    NA
    Hairs between stem nodes
    the stem has no hairs between the nodes
    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
    20–70 cm
    Tendril origin
    NA
    Tendrils
    the plant does not have tendrils

Wetland status

Not classified

In New England

Distribution

Connecticut
present
Maine
absent
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.

Massachusetts
rare to uncommon (S-rank: S2S3)
New Hampshire
rare (S-rank: S2), threatened (code: T)
Vermont
uncommon (uncertain) (S-rank: S3?)

From Flora Novae Angliae dichotomous key

1.  Caulophyllum giganteum (Farw.) Loconte & Blackwell N

early blue cohosh. Caulophyllum thalictroides (L.) Michx. var. giganteum Farw. • CT, MA, NH, VT. Mesic, deciduous forests, often rich and rocky, high-terrace floodplain forests. Caulophyllum giganteum flowers ca. 10–15 days ealier than C. thalictroides when both are present at 
the same site. The two species differ somewhat vegetatively. The ultimate leaf segments of 
 C. giganteum are 5–10 cm long and first leaf is 2- or, more commonly, 3-times pinnately divided. The ultimate leaf segments of C. thalictroides are 3–8 cm long and the first leaf is 
3- or, more commonly, 4-times pinnately divided.

Native to North America?

Yes

Sometimes confused with

Caulophyllum thalictroides:
flowers appearing with the leaves, mostly numbering 5-70 per inflorescence, and with usually yellow to yellow-green sepals 3-6 mm long (vs. C. giganteum, with flowers appearing before expansion of the leaves, mostly numbering 4-18 per inflorescence, and with purple to purple-brown sepals 6-9 mm long).

Synonyms

  • Caulophyllum thalictroides (L.) Michx. var. giganteum Farw.

Family

Berberidaceae

Genus

Caulophyllum