Heracleum maximum Bartr.

American cow-parsnip

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New England Distribution

Adapted from BONAP data

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North America Distribution

Adapted from BONAP data

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Facts About

American cow-parsnip is found in a variety of habitats from river banks to subalpine meadows in all New England states. It is the largest, native species in the carrot family (Apiaceae) in the United States, growing up to 8 feet (2.5 m) in height. It has large umbels of white flowers and hollow, grooved stems. This species was very widely used by Native Americans for food, medicine, to fashion toys, as an insect repellant, and in sorcery.

Habitat

Alpine or subalpine zones, anthropogenic (man-made or disturbed habitats), meadows and fields, shores of rivers or lakes

Characteristics

Habitat
  • terrestrial
  • wetlands
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont
Flower petal color
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 has lobes, or it has both teeth and lobes
Flower symmetry
  • there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
  • 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
both the petals and sepals are separate and not fused
Stamen number
5
Fruit type (general)
the fruit is dry but does not split open when ripe
Fruit length
5–12 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
    • NA
    • there are two or more ways to evenly divide the calyx (the calyx is radially symmetrical)
    Carpel hairs
    • the carpels have hairs, but they are not thick and woolly
    • the carpels have no hairs
    Carpels fused
    the carpels are 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
    Filament surface
    the filament is smooth, with no hairs or scales
    Flower description
    the flower has an inferior ovary, with or without a hypanthium
    Flower petal color
    white
    Flower reproductive parts
    • the flower has both pollen- and seed-producing parts
    • the flower has either only pollen- or only seed-producing parts
    Flower symmetry
    • there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
    • there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)
    Flowers sunken into stem
    no
    Form of style
    the flower has two or more completely separate styles
    Fused stamen clusters
    NA
    Fusion of sepals and petals
    both the petals and sepals are separate and not fused
    Hairs on inflorescence
    the axis of the inflorescence has hairs entirely without glands
    Horns in hoods (Asclepias)
    NA
    Hypanthium
    the flower does not have a hypanthium
    Inflorescence length
    30–100 mm
    Inflorescence one-sided
    the flowers are arrayed in a spiral around the inflorescence axis or branches, or occur singly, or in several ranks
    Inflorescence width
    100–200 mm
    Inner tepals (Rumex)
    NA
    Interior flower disk
    the flower has an interior disc
    Length of flower stalk
    6–20 mm
    Length of peduncle
    50–200 mm
    Marks on petals
    there are no noticeable marks on the petals
    Nectar spur
    the flower has no nectar spurs
    Number of branches in umbel
    12–30
    Number of carpels
    2
    Number of pistils
    1
    Number of sepals, petals or tepals
    there are five petals, sepals, or tepals in the flower
    Number of styles
    2
    Ovary position
    the ovary is below the point of petal and/or sepal attachment
    Petal and sepal arrangement
    • the flower includes only one cycle of petals or sepals
    • the flower includes two cycles of petal- or sepal-like structures
    Petal and sepal colors
    white
    Petal appearance
    the petals are thin and delicate, and pigmented (colored other than green or brown)
    Petal folding in bud
    the petals in bud meet exactly at the margins without overlapping (valvate)
    Petal folds or pleats
    the petals of the flower do not have folds or plaits
    Petal hairs (Viola)
    NA
    Petal number
    5
    Petal shape
    • the petal outline is another shape
    • the petal outline is obovate (roughly egg-shaped, but with the widest point above the middle of the leaf blade)
    Petal tip shape
    the petal tip is retuse (with a blunt or rounded apex and a notch at the center)
    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
    • NA
    • 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 color
    • NA
    • green to brown
    Sepal number
    0
    Sepal shape
    • the sepal outline is lanceolate (lance-shaped; narrow, gradually tapering from the base to the tip)
    • the sepal outline is roughly triangular
    Sepals fused only to sepals
    the sepals are fused to each other (not other flower parts), at least near their bases
    Stamen attachment
    the stamens are not attached to the petals or tepals
    Stamen number
    5
    Stamen position relative to petals
    the stamens are lined up with the sepals
    Stamens fused
    the stamens are not attached to one another
    Staminodes
    there are no staminodes on the flower
    Style petal-like
    the styles are not petal-like
    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
    Carpel beak length
    0–2 mm
    Fruit (pyxis) dehiscence
    NA
    Fruit cross-section
    the fruit is at least somewhat flattened
    Fruit features (Brassicaceae)
    NA
    Fruit length
    5–12 mm
    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)
    • the fruit is spherical
    Fruit stalk orientation
    the fruits point upward or spread or curve outward
    Fruit type (general)
    the fruit is dry but does not split open when ripe
    Fruit type (specific)
    the fruit is a schizocarp (when dry it splits into sections, each holding one or more seeds)
    Fruit width
    4–10 mm
    Hairs on fruit
    • the fruits are not hairy
    • the fruits have hairs on them
    Legumes (Fabaceae)
    NA
    Mericarp length
    7–12 mm
    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 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
    the fruit is flattened parallel to the commissure
    Schizocarpic fruit segments
    2
    Seed number
    2
    Septum in fruit (Brassicaceae)
    NA
    Wings on fruit
    the fruit has one or more 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
    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 for two years
    • 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 is a thickened taproot on the plant
  • Leaves
    Bracteole shape
    the bracteoles are lanceolate (widest below the middle, and tapering at both ends)
    Bracteoles
    the plant has bracteoles between the primary bracts and the flowers
    Bracts in plantain (Plantago)
    NA
    Final leaf segment length (compound lvs only)
    50–600 mm
    Final leaf segment width (compound lvs only)
    100–400 mm
    Floral bracts
    the flower has one or more bracts associated with it
    Flower bract length
    10–20 mm
    Hairs on underside of leaf
    the underside of the leaf is fuzzy or hairy
    Hairs on upper side of leaf
    • the upper side of the leaf is fuzzy or hairy
    • the upper side of the leaf is not hairy, or it has very few hairs
    Hooked hairs on underside of leaf
    no
    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
    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)
    Leaf blade bloom
    the underside of the leaf has no noticeable bloom
    Leaf blade edges
    the edge of the leaf blade has lobes, or it has both teeth and lobes
    Leaf blade hairs
    the leaf blade has simple hairs with no glands, and not tangled or wooly
    Leaf blade length
    50–600 mm
    Leaf blade primary vein pattern
    the major veins radiate out from one point at the base
    Leaf blade shape
    • the leaf blade is cordate (heart-shaped with backward-facing rounded lobes), or sagittate (arrow-shaped with backward-facing pointed lobes)
    • the leaf blade is orbicular (roughly circular, as wide as long)
    • the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
    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 blade width
    200–500 mm
    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
    the hairs are standing up straight or curved in different directions
    Leaf spines
    there are no spines on the leaf edges
    Leaf stalk
    the leaves have leaf stalks
    Leaf stalk attachment to leaf
    the petiole attaches at the basal margin of the leaf blade
    Leaf stalk base
    the petiole base clasps the stem or sheathes the stem
    Leaf stalk length
    100–400 mm
    Leaf teeth and lobes
    the leaf blade margin has forward-pointing teeth
    Leaf type
    the leaves are compound (made up of two or more discrete leaflets
    Leaf types
    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 lower leaves are larger, toothier, and/or on longer stalks than the upper leaves
    Leaflet number
    3–7
    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
    • NA
    • 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
    Stipels
    there are no stipels at the bases of the petiolules
    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
  • Place
    Habitat
    • terrestrial
    • wetlands
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    • Vermont
    Specific habitat
    • alpine or subalpine zones
    • man-made or disturbed habitats
    • meadows or fields
    • shores of rivers or lakes
  • Scent
    Plant odor
    the plant has an unpleasant smell
  • Stem, shoot, branch
    Branched tendrils
    NA
    Direction of stem hairs
    • the hairs are pressed flat against the plant, pointing towards the plant's tip
    • the hairs point mostly upwards to outwards
    Flowering stem cross-section
    the flowering stem is circular, or with lots of small angles so that it is roughly circular
    Flowering stem width
    4–20 mm
    Hair between stem nodes
    the stem has hairs between the nodes
    Hairs between stem nodes
    at least some of the hairs on the stem are tangled, matted or woolly
    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
    100–300 cm
    Stem bloom
    there is no powdery or waxy film on the stem
    Stem hair distribution
    the hairs on the stem are distributed more of less uniformly
    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
    Tendril origin
    NA
    Tendrils
    the plant does not have tendrils
    Wings on stem
    the stem does not have wings on it

Wetland Status

Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)

New England Distribution and Conservation Status

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
unranked (S-rank: SNR)

Native to North America?

Yes

Sometimes Confused With

Heracleum mantegazzianum:
umbel with mostly 50-150 primary branches and fruit on a stalk 15-40 mm long (vs. H. maximum, with umbel with 15-45 primary branches and fruit on a stalk 6-20 mm long).

Synonyms

  • Heracleum lanatum Michx.
  • Heracleum sphondylium ssp. montanum (Schleich. ex Gaudin) Briq.
  • Heracleum sphondylium var. lanatum (Michx.) Dorn

Family

Apiaceae

Genus

Heracleum

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Information from Dichotomous Key of Flora Novae Angliae

2.  Heracleum maximum Bartr. N

American cow-parsnip. Heracleum lanatum Michx.; H. sphondylium L. ssp. montanum (Schleich. ex Gaudin) Briq.; H. sphondylium L. var. lanatum (Michx.) Dorn • CT, MA, ME, NH, RI, VT. River banks, riparian terraces, meadows, roadside ditches, fields, subalpine meadows.