Asclepias syriaca L.

common milkweed

New England Distribution

Adapted from BONAP data

Where native and non-native distributions co-occur in a county, only the native distribution is shown.

North America Distribution

Adapted from BONAP data

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Facts About

Common milkweed is found in fields and roadsides in all New England states. Native Americans used the young leaves and stems as well as the buds of this species as food. The outer bark was also used to make cord, thread, and bowstrings.

Habitat

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

Characteristics

Habitat
terrestrial
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont
Flower petal color
  • blue to purple
  • green to brown
  • pink to red
Leaf type
the leaves are simple (lobed or unlobed but not separated into leaflets)
Leaf arrangement
opposite: there are two leaves per node along the stem
Leaf blade edges
the edge of the leaf blade is entire (has no teeth or lobes)
Flower symmetry
there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
Number of sepals, petals or tepals
there are five petals, sepals or tepals in the flower
Fusion of petals
the petals are fused into a corolla tube
Stamen number
5
Fruit type (general)
the fruit is dry and splits open when ripe
Fruit length
80–110 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 some other type of opening
    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
    Cleistogamous flowers
    there are no cleistogamous flowers on the plan
    Corolla palate
    no
    Corona lobe length
    4–5 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 diameter
    3–6 mm
    Flower petal color
    • blue to purple
    • green to brown
    • 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
    Fused stamen clusters
    there is one cluster of fused stamens
    Fusion of petals
    the petals are fused into a corolla tube
    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
    Hypanthium length
    0 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
    50–100 mm
    Inner tepals (Rumex)
    NA
    Length of flower stalk
    30–60 mm
    Length of peduncle
    50–100 mm
    Marks on petals
    there are no noticeable marks on the petals
    Nectar spur
    the flower has no nectar spurs
    Number of carpels
    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
    Perianth shape
    the perianth is rotate (platter-shaped, the corolla flattened, circular, with nearly horizontally spreading lobes)
    Petal and sepal arrangement
    the flower includes three distinct cycles of petal- or sepal-like structures
    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 length
    7–10 mm
    Petal length relative to sepals
    the petals are longer than the sepals
    Petal number
    5
    Petal shape
    • the petal outline is oblong (rectangular, but with rounded ends)
    • the petal outline is ovate (widest below the middle and broadly tapering at both ends)
    Petal tip shape
    the petal tip is acute (sharply pointed)
    Petal tips (Cuscuta)
    NA
    Petal width
    3–4 mm
    Raceme attachment (Veronica)
    NA
    Reproductive system
    all the flowers have both carpels and stamens (synoecious)
    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 (Oenothera)
    NA
    Sepal color
    green to brown
    Sepal number
    5
    Sepal orientation
    the sepals are curved outwards and downwards from the corolla
    Sepals fused only to sepals
    the sepals are fused to each other (not other flower parts), at least near their bases
    Stamen appendages
    there are awns, spurs, or some other appendages on the stamens
    Stamen attachment
    the stamens are not attached to the petals or tepals
    Stamen number
    5
    Stamens fused
    the stamens are attached to one another at or near their bases
    Style petal-like
    the styles are not petal-like
    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 splitting
    NA
    Carpel beak length
    0 mm
    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
    80–110 mm
    Fruit locules
    one
    Fruit shape
    the fruit is ovoid (egg-shaped)
    Fruit stalk orientation
    the fruits curve or droop downwards
    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)
    Fruit width
    20–30 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 have hairs on them
    Legumes (Fabaceae)
    NA
    Mericarp length
    0 mm
    Mericarp segment shape (Desmodium)
    NA
    Other markings on berry
    NA
    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 are armed with thorns-like defensive structures
    • 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)
    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 caudex (the root mass is firm and hardened at the top)
    • there is a thickened taproot on the plant
  • Leaves
    Bracteole number (Apiaceae)
    0
    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
    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
    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 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 hairs
    the leaf blade has tangled or woolly-looking hairs
    Leaf blade length
    150–230 mm
    Leaf blade primary vein pattern
    the secondary veins branch off at intervals from the primary vein
    Leaf blade shape
    • the leaf blade is 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 coriaceous (has a firm, leathery 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
    50–90 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
    • the hairs are standing up straight or curved in different directions
    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 stalk length
    5–15 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 acute (sharply pointed)
    Leaf type
    the leaves are simple (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 (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
    Teeth per side of leaf blade
    0
  • Place
    Habitat
    terrestrial
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    • Vermont
    Specific habitat
    • edges of forests
    • man-made or disturbed habitats
    • meadows or fields
  • 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
    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
    100–150 cm
    Stem bloom
    the stem has a powdery or waxy film on it that can be rubbed away
    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

Occurs most often in non-wetlands, but rarely in wetlands. (Wetland indicator code: FACU-)

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

Synonyms

  • Asclepias intermedia Vail
  • Asclepias syriaca var. kansana (Vail) Palmer & Steyermark

Family

Apocynaceae

Genus

Asclepias

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Information from Dichotomous Key of Flora Novae Angliae

6.  Asclepias syriaca L. N

common milkweed. Asclepias intermedia Vail; A. syriaca L.  var. kansana (Vail) Palmer & Steyermark • CT, MA, ME, NH, RI, VT. Fields, roadsides, open rights-of-way.