Heracleum maximum — American cow-parsnip

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)

In New England

From Flora Novae Angliae dichotomous key