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• All other herbaceous, flowering dicots
• Asclepias purpurascens

Asclepias purpurascens — purple milkweed

Facts

Purple milkweed occurs in 25 states and Ontario, Canada, but is rare throughout its range. In New England it is currently known only from Connecticut and Massachusetts, although it was formerly also found in Rhode Island and New Hampshire. The number of populations known in New England has fallen from 82 historically to only a few today. It is found in oak-pine associations, woodland edges, roadsides and dry fields.

Habitat

Anthropogenic (man-made or disturbed habitats), forest edges, meadows and fields

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 some other type of opening

  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)

  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

  Cilia on petals

  the petal margins do not have cilia

  Cleistogamous flowers

  there are no cleistogamous flowers on the plan

  Corolla palate

  no

  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 appearance

  the flowers appear after the leaves have appeared

  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

  • blue to purple
  • pink to red

  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 flower has two or more completely separate styles

  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

  • the axis of the inflorescence has hairs entirely without glands
  • the axis of the inflorescence has no hairs on it

  Horns in hoods (Asclepias)

  the corona horns are shorter than, or equal in length to, the corona hoods

  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

  Inflorescence type

  the inflorescence is a simple umbel (with an axis so short it appears the flowers all originate from the same point)

  Inner tepals (Rumex)

  NA

  Marks on petals

  there are no noticeable marks on the petals

  Nectar spur

  the flower has no nectar spurs

  Number of pistils

  2

  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

  Petal and sepal arrangement

  the flower includes three distinct cycles of petal- or sepal-like structures

  Petal and sepal colors

  • blue to purple
  • pink to red

  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 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 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 another shape
  • the petal outline is elliptic (shaped like an ellipse; widest near the middle and tapering at both ends)
  • the petal outline is oblong (rectangular, but with rounded ends)

  Petal tip shape

  • the petal tip is acute (sharply pointed)
  • the petal tip is obtuse (bluntly pointed)
  • the petal tip is rounded

  Petal tips (Cuscuta)

  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 color

  green to brown

  Sepal features

  the sepals do not have any of the mentioned special features

  Sepal number

  5

  Sepal orientation

  the sepals are curved outwards and downwards from the corolla

  Sepal uniformity

  all the sepals are about the same size

  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
  • 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

  Staminodes

  there are no staminodes on the flower

  Style petal-like

  the styles are not petal-like

  Style relative length

  the stigma protrudes beyond the mouth of the corolla

  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

  NA

  Capsule splitting

  NA

  Fruit (pyxis) dehiscence

  NA

  Fruit beak length

  0 mm

  Fruit cross-section

  the fruit is round in cross-section

  Fruit features (Brassicaceae)

  NA

  Fruit length

  100–160 mm

  Fruit locules

  one

  Fruit shape

  • the fruit is ellipsoid (widest in the middle and tapering to each end)
  • the fruit is obtriangular (roughly traingular, but with the stem at one of the points)

  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 follicle (has one ovary that splits along one side to release the seeds)

  Hair type on fruit

  • NA
  • 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
  • the fruits have hairs on them

  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 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

  Seeds comose

  hairs are present

  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 milky and opaque, and may be white or colored

  Sap color

  the sap is white

• 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 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 edges

  NA

  Bracteole number (Apiaceae)

  0

  Bracteole shape

  NA

  Bracteoles

  there are no bracteoles on the plant

  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

  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

  Hooked hairs on underside of leaf

  no

  Inflated hairs on leaf

  the leaf blade does not have inflated hairs on it

  Leaf arrangement

  opposite: there are two leaves 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 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 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

  100–150 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 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 is herbaceous (has a leafy 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 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 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)

  Leaf tip

  • the tip of the leaf blade is acute (sharply pointed)
  • the tip of the leaf blade is obtuse (bluntly pointed)

  Leaf tufts in axils

  there are no clusters of smaller leaves growing out of axils

  Leaf type

  the leaves are simple (i.e., lobed or unlobed but not separated into 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 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 are two leaves 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 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
  • Massachusetts
  • New Hampshire
  • Rhode Island

  Specific habitat

  • edges of forests
  • man-made or disturbed habitats
  • meadows or fields

• Scent

  Plant odor

  the plant does not have much of a smell

• Stem, shoot, branch

  Branched tendrils

  NA

  Flowering stem cross-section

  • the flowering stem is circular, or with lots of small angles so that it is roughly circular
  • the flowering stem is roughly square

  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

  Up to 100 cm

  Stem hair distribution

  • NA
  • the hairs on the stem are distributed more of less uniformly

  Stem nodes swollen

  the stem is not swollen at the nodes

  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 non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae