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• All other flowering non-woody plants
• All other herbaceous, flowering dicots
• Menyanthes trifoliata

Menyanthes trifoliata — bog bean, buck-bean

Facts

Buck-bean typically grows in shallow water of bogs and fens. Extracts of the plant were once used to treat scurvy, and the leaves were sometimes used in Europe as a substitute for hops in beer.

Habitat

Fens, meadows and fields, wetland margins (edges of wetlands)

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 length

  1.8–2 mm

  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

  Anther tube length

  0 mm

  Calyx symmetry

  there are two or more ways to evenly divide the calyx (the calyx is radially symmetrical)

  Carpel hairs

  the carpels have no hairs

  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 tube of the flower is curved upwards

  Corolla palate

  no

  Corona lobe length

  0 mm

  Epicalyx

  the flower does not have an epicalyx

  Epicalyx number of parts

  0

  Filament length

  5.5–6.5 mm

  Filament surface

  the filament is smooth, with no hairs or scales

  Flower description

  • the flower has a superior ovary, and lacks a hypanthium
  • the flower has an inferior ovary, with or without a hypanthium

  Flower diameter

  15 mm

  Flower length

  14–17 mm

  Flower number

  10–20

  Flower orientation

  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 are two or more ways to evenly divide the flower (the flower is radially symmetrical)

  Flowers sunken into stem

  no

  Form of style

  the style is lobed at the tip, and unbranched

  Fringed petal edges

  the petals are fringed

  Fused stamen clusters

  NA

  Fusion of sepals and petals

  • both the petals and sepals are separate and not fused
  • 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 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

  Length of flower stalk

  5–10 mm

  Length of peduncle

  300–350 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

  0

  Number of carpels

  2

  Number of pistils

  1

  Number of sepals, petals or tepals

  there are five petals, sepals, or tepals in the flower

  Ovary position

  • the ovary is above the point of petal and/or sepal attachment
  • the ovary is below the point of petal and/or sepal attachment

  Perianth shape

  the perianth is salverform (with a slender basal tube and a more-or-less horizontally spreading mouth)

  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 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 glandular dots or scales

  no

  Petal hairs (Viola)

  NA

  Petal hairs on inner/upper surface

  there are hairs on the inner/upper petal surface

  Petal length

  7.5–10 mm

  Petal length relative to sepals

  the petals are longer than the sepals

  Petal nectaries

  the petals do not have nectaries

  Petal number

  5

  Petal shape

  • the petal outline is elliptic (shaped like an ellipse; widest near the middle and tapering at both ends)
  • the petal outline is lanceolate (lance-shaped; narrow, gradually tapering from the base to the tip)

  Petal tip shape

  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

  • green to brown
  • pink to red

  Sepal features

  NA

  Sepal length

  4–5 mm

  Sepal number

  5

  Sepal orientation

  • the sepals are curved outwards and downwards from the corolla
  • the sepals are slightly curved outwards from the corolla

  Sepal relative length

  • the sepal lobes are approximately the same length as the fused portion
  • the sepal lobes are longer than the fused portion

  Sepal shape

  the sepal outline is ovate (widest below the middle and broadly tapering at both ends)

  Sepal texture

  the sepals are fleshy or spongy

  Sepal tip shape

  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
  • the sepals are separate from one another

  Spur length

  0 mm

  Spur number

  NA

  Stamen appendages

  stamen appendages are absent

  Stamen attachment

  the stamens are attached at or near the bases of the petals or tepals

  Stamen lengths differ

  the stamens are all approximately the same length

  Stamen morphology

  the stamens within each cycle are the same

  Stamen number

  5

  Stamen position relative to petals

  the stamens are lined up with the petals

  Stamen relative length

  anything

  Stamens fused

  the stamens are not attached to one another

  Staminodes

  there are no staminodes on the flower

  Stigma position

  the stigmas are positioned at the tip of the style

  Style length

  6–12 mm

  Style petal-like

  the styles are not petal-like

  Surface of ovary

  the ovary surface has no points, bumps or wrinkles

  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

  the capsule has two prominent ribs or wings

  Capsule splitting

  the capsule splits by two main valves, teeth or pores

  Carpel beak length

  0 mm

  Fruit (pyxis) dehiscence

  NA

  Fruit features (Brassicaceae)

  NA

  Fruit length

  6–9 mm

  Fruit length relative to sepals

  the fruit is longer than its associated sepals

  Fruit locules

  one

  Fruit shape

  the fruit is spherical

  Fruit stalk orientation

  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)

  Fruit width

  6–7 mm

  Hair type on fruit

  the hairs on the fruits are simple (not branched), don’t have glands, and are not woolly

  Hairs on fruit

  the fruits are not hairy

  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 parietal placentation, where ovules develop on the wall or slight outgrowths of the wall forming broken partitions within a compound ovary

  Rows of seeds in fruit (Brassicaceae)

  NA

  Schizocarpic fruit compression

  NA

  Schizocarpic fruit segments

  0

  Seed relative length

  the seed is about as long as it is wide

  Seed surface

  the seed is smooth or without clear markings

  Seeds comose

  no hairs

  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 clear and watery

  Sap color

  the sap is clear

• Growth form

  Growth form

  the plant is an herb (it has self-supporting stems)

  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

  Spines on plant

  the plant has no spines

  Underground organs

  the plant has a rhizome (a horizontal underground stem with roots growing from it)

• Leaves

  Bracteole number (Apiaceae)

  0

  Bracts in plantain (Plantago)

  NA

  Final leaf segment length (compound lvs only)

  30–100 mm

  Floral bracts

  the flower has one or more bracts associated with it

  Flower bract length

  5–7 mm

  Hairs on leaf stalk

  the petiole has no hairs on it

  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

  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
  • basal: the leaves are growing only at the base of the plant

  Leaf blade base

  the leaf has a distinct leaf stalk (petiole)

  Leaf blade base shape

  the base of the leaf blade is cuneate (wedge-shaped, tapers to the base with relatively straight, converging edges), or narrow

  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 flatness

  the leaf is flat (planar) at the edges

  Leaf blade hairs

  the leaf blade has simple hairs with no glands, and not tangled or wooly

  Leaf blade primary vein pattern

  the secondary veins branch off at intervals from the primary vein

  Leaf blade shape

  • the leaf blade is elliptic (widest near the middle and tapering at both ends)
  • the leaf blade is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
  • 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 texture

  the leaf blade has a fleshy or spongy texture

  Leaf blade vein pattern

  the major veins of the leaf blade branch, but do not rejoin

  Leaf blade veins

  the leaf blade has one main vein running from the base towards the tip (it may or may not have secondary veins)

  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 shiny

  the upper side of the leaf is dull or slightly shiny

  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

  70–200 mm

  Leaf teeth and lobes

  • the edge of the leaf blade is entire (has no teeth or lobes)
  • the leaf blade margin is wavy, but does not have teeth

  Leaf tip

  • the tip of the leaf blade is acute (sharply pointed)
  • the tip of the leaf blade is rounded, with no point

  Leaf type

  the leaves are compound (made up of two or more discrete leaflets

  Leaf types

  NA

  Leaf variation

  the lower leaves are larger, toothier, and/or on longer stalks than the upper leaves

  Leaflet number

  3

  Leaflet petiolules

  the leaflets of the compound leaf have petiolules

  Leaves per node

  • the leaves are growing only at the base of the plant (i.e., basal)
  • there are no apparent leaves except on the reproductive stems

  Pinnately compound leaf type

  NA

  Specific leaf type

  the leaf has lobes that radiate from the base, somewhat like a hand

  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

  Teeth per side of leaf blade

  0

• Place

  Habitat

  • terrestrial
  • wetlands

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont

  Specific habitat

  • edges of wetlands
  • fens
  • meadows or fields

• 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

  no

  Leaves on stem

  the flowering stem has no leaves above the base

  Length of hairs between stem nodes

  0 mm

  Plant height

  12–35 cm

  Stem bloom

  there is no powdery or waxy film on the stem

  Stem hair distribution

  NA

  Stem orientation

  the stems are upright or angled outwards

  Stem roughness between nodes

  • NA
  • the stem does not feel rough

  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)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae