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• All other herbaceous, flowering dicots
• Persicaria amphibia

Persicaria amphibia — water smartweed

Facts

water smartweed is a native perennial that inhabits still or slow moving water of lakes, rivers, marshes and swamps, and is variable in habit, growing underwater, floating or emergent. The inflorescence is a dense cluster of many five-lobed pink flowers.

Habitat

Anthropogenic (man-made or disturbed habitats), lacustrine (in lakes or ponds), marshes, riverine (in rivers or streams), shores of rivers or lakes, swamps, 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 color

  there is a noticeable pink, reddish or purplish tint to the anthers

  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 growth after flowering

  the calyx does not grow to cover or partially cover the fruit

  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

  Cilia on petals

  the petal margins do not have cilia

  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 a superior ovary, and lacks a hypanthium

  Flower orientation

  the flower points upwards or is angled outwards

  Flower petal color

  pink to red

  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)

  Flowers sunken into stem

  no

  Form of style

  the style is branched above the base

  Fringed petal edges

  the petals are not fringed

  Fusion of sepals and petals

  the petals or the sepals are fused into a cup or tube

  Hairs on inflorescence

  • at least some of the hairs on the axis of the inflorescence have glands
  • the axis of the inflorescence has no hairs on it

  Horns in hoods (Asclepias)

  NA

  Hypanthium

  • the flower does not have a hypanthium
  • the flower has a hypanthium

  Inflorescence length

  10–150 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

  8–20 mm

  Inner tepals (Rumex)

  NA

  Length of flower stalk

  0.5–1.5 mm

  Length of peduncle

  10–50 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

  Number of styles

  2

  Ovary position

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

  Perianth shape

  the perianth is campanulate (bell-shaped, with a tube about as long as wide, flaring at the mouth)

  Petal and sepal arrangement

  the flower includes two cycles of petal- or sepal-like structures

  Petal and sepal colors

  pink to red

  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 glandular dots or scales

  no

  Petal hairs (Viola)

  NA

  Petal hairs on inner/upper surface

  there are no hairs on the inner/upper petal surface

  Petal length

  4–6 mm

  Petal number

  2

  Petal shape

  • the petal outline is elliptic (shaped like an ellipse; widest near the middle and tapering at both ends)
  • 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 acute (sharply pointed)
  • the petal tip is rounded

  Petal tips (Cuscuta)

  NA

  Raceme attachment (Veronica)

  NA

  Reproductive system

  • all the flowers have both carpels and stamens (synoecious)
  • all the flowers on each plant have only carpels or only stamens, with only one type being present on each plant (dioecious)

  Scales inside corolla

  no

  Sepal and petal color

  the petals and sepals are similar

  Sepal appearance

  the sepals resemble petals in color and texture

  Sepal appendages

  the sepals do not have appendages on them

  Sepal appendages (Oenothera)

  NA

  Sepal cilia

  the sepals do not have cilia

  Sepal color

  pink to red

  Sepal features

  NA

  Sepal length

  4–6 mm

  Sepal number

  3

  Sepal shape

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

  Sepal texture

  the sepals are either very thin but flexible, like a membrane, or they are leaf-like in texture

  Sepal tip shape

  • the sepal tip is acute (is sharply pointed)
  • the sepal tip is rounded

  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

  Stamen morphology

  the stamens within each cycle are the same

  Stamen number

  5

  Stamen relative length

  • anything
  • anything

  Staminodes

  there are no staminodes on the flower

  Style length

  Up to 4 mm

  Style petal-like

  the styles are not petal-like

  Style relative length

  • the stigma does not protrude beyond the mouth of the corolla
  • the stigma protrudes beyond the mouth of the corolla

  Umbel flower reproductive parts

  NA

  Upper lip of bilabiate corolla

  NA

• Fruits or seeds

  Achene relative orientation

  the achenes are perpendicular to the plane of the perianth (vertical)

  Achene shape

  • the achenes are circular in outline
  • the achenes are oval in outline

  Achene surface (Polygonum)

  NA

  Achene type

  the fruit is an achene (dry, indehiscent, and usually one-seeded)

  Berry color

  NA

  Capsule color (Viola)

  NA

  Capsule ribs

  NA

  Capsule splitting

  NA

  Carpel beak length

  0 mm

  Fruit (pyxis) dehiscence

  NA

  Fruit cross-section

  the fruit is at least somewhat flattened

  Fruit features (Brassicaceae)

  NA

  Fruit length

  2–3 mm

  Fruit length relative to sepals

  the fruit is shorter than its associated sepals

  Fruit locules

  one

  Fruit shape

  the fruit is flat or strongly compressed

  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 an achene (dry, usually one-seeded, does not separate or split open at maturity)

  Fruit width

  1.5–2.6 mm

  Hair type on fruit

  NA

  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 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

  Seed number

  1

  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)

  Horizontal rooting stem

  • the plant does not have stolons
  • the plant has stolons

  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

  Underground organs

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

• Leaves

  Bracteole number (Apiaceae)

  0

  Bracteoles

  the plant has bracteoles between the primary bracts and the flowers

  Bracts in plantain (Plantago)

  NA

  Final leaf segment length (compound lvs only)

  0 mm

  Final leaf segment length to width ratio (compound lvs only)

  0

  Final leaf segment width (compound lvs only)

  0 mm

  Floral bract texture

  NA

  Floral bracts

  the flower does not have bracts

  Flower bract length

  0 mm

  Hairs on leaf stalk

  • the petiole has hairs on it
  • the petiole has no hairs on it

  Hairs on underside of leaf

  • the underside of the leaf is fuzzy or hairy
  • 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 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)
  • the leaf has no stalk

  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
  • the base of the leaf blade is rounded

  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 length

  20–230 mm

  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 lanceolate (lance-shaped; widest below the middle and tapering at both ends)
  • the leaf blade is oblong (rectangular but with rounded ends)
  • 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 blade width

  10–80 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 flat against the leaf surface, mostly pointing towards the leaf tip

  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
  • the leaves have no leaf stalks, but attach directly to the stem

  Leaf stalk attachment to leaf

  • NA
  • 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 stalk length

  1–70 mm

  Leaf teeth and lobes

  the edge of the leaf blade is entire (has no teeth or lobes)

  Leaf tip

  • the tip of the leaf blade is acuminate (tapers to a long, thin point)
  • the tip of the leaf blade is acute (sharply pointed)

  Leaf type

  the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)

  Leaf types

  NA

  Leaf variation

  the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem

  Leaflet number

  0

  Leaflet petiolules

  NA

  Leaves per node

  there is one leaf per node along the stem

  Pinnately compound leaf type

  NA

  Specific leaf type

  the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)

  Stipels

  NA

  Stipule features

  • at least some of the stipules on a plant are expanded and with leaf-like color and/or texture at their tips
  • glabrous on the surface
  • the stipules are hairy with hairs standing out at a 45 to 90 degree angle, or pressed to the stipule surface
  • the stipules are straight (or somewhat slanted) across the top
  • the stipules do not have tiny hairs (cilia) at their tips
  • the stipules have a fringe of cilia along the top edge

  Stipule length

  5–50 mm

  Stipule shape

  the stipules are tubular (cylindrical and hollow)

  Stipules

  the plant has stipules

  Teeth per side of leaf blade

  0

• Place

  Habitat

  • aquatic
  • terrestrial
  • wetlands

  New England state

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

  Specific habitat

  • edges of wetlands
  • in lakes or ponds
  • in rivers or streams
  • man-made or disturbed habitats
  • marshes
  • shores of rivers or lakes
  • swamps

• Scent

  Plant odor

  the plant does not have much of a 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

  Hair between stem nodes

  • the stem has hairs between the nodes
  • the stem has no hairs between the nodes

  Hairs between stem nodes

  • the hairs on the stem are plain, without glands or branches, and not tangled
  • 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

  20–300 cm

  Stem bloom

  there is no powdery or waxy film on the stem

  Stem nodes swollen

  the stem is swollen at the nodes

  Stem orientation

  • the stems are upright or angled outwards
  • the stems trail at the base, but may turn upwards at the tips

  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