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- Asteraceae Group 1
- Sonchus
- Sonchus oleraceus
Sonchus oleraceus — common sow-thistle
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Facts
Common sow-thistle is native to Europe and introduced worldwide, including across North America. Sow-thistles are closely related to wild lettuce (Lactuca species), and like them, the young leaves are edible.
Habitat
Anthropogenic (man-made or disturbed habitats), meadows and fields
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
Characteristics
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Leaf type
- leaves are simple (lobed or unlobed but not separated into leaflets)
- Leaf arrangement
- alternate: there is one leaf per node along the stem
- Leaf blade edges
-
- the edge of the leaf blade has lobes, or it has both teeth and lobes
- the edge of the leaf blade has no teeth or lobes
- the edge of the leaf blade has teeth
- Flower type in flower heads
- the flower head has ray flowers only, meaning all of the individual flowers of the flower head have a strap-shaped ray, which may or may not have teeth at the very tip of the ray
- Ray flower color
-
- orange
- yellow
- Tuft or plume on fruit
- at least a part of the plume is made up of fine bristles
- Spines on plant
- there are spines on the plant
- Leaf blade length
- 60–350 mm
- Disk flower number
- 0
-
Flowers
- Bases of bract appendages
- NA
- Bract cycle number
- there are three or more cycles of bracts
- Bract outer side hair type
-
- the bracts are hairy on their outer surfaces, with hairs having glands (a swelling at the tip of the hair)
- the bracts are hairy, with simple hairs on their outer surface
- the bracts are not hairy on their outer surface
- Bract outer side hairs
-
- the bracts are hairy on their outer surfaces
- the bracts are not hairy on their outer surfaces
- Bract tip shape
- the tips of the bracts acute (have a sharp point)
- Bracts
- there are at least two distinct forms of bracts in different cycles
- Disk flower color
- NA
- Disk flower lobe number
- 0
- Disk flower number
- 0
- Disk flower proportions
- NA
- Disk flower reproductive parts
- NA
- Disk flower shape
- NA
- Flower head outer flowers
- at the outer edge of the flower head, each flower has a single enlarged lobe or strap
- Flower head platform
- the base has no bristles or papery scales
- Flower head platform surface
- NA
- Flower type in flower heads
- the flower head has ray flowers only, meaning all of the individual flowers of the flower head have a strap-shaped ray, which may or may not have teeth at the very tip of the ray
- Height of flower head base
- 9–13 mm
- Inflorescence branching (Solidago)
- NA
- Inflorescence shape
- the inflorescence is flat-topped in profile
- Ovary beak
- there is no beak on the ovary
- Ovary cross-section
- the ovary is compressed (flattened)
- Ovary hair type
- the ovary has no hairs on it
- Ovary hairs
- the ovary has no hairs on it
- Ovary profile
- in profile, the ovary is lance-shaped, but widest above the middle
- Ovary surface
- the ovary surface is textured with tiny points, bumps or wrinkles
- Peduncle hair type
- the hairs on the peduncles have glands at their tips
- Peduncle hairs
-
- the peduncles are hairy
- the peduncles have no hairs
- Ray flower color
-
- orange
- yellow
- Ray flower reproductive parts
- the ray flowers have both carpels and stamens
- Ray flowers
- more than 50
- Reproductive system
- all the flowers on the plant contain both carpels and stamens
- Rim at top of ovary
- the central flowers have no disk-shaped platform above the ovary
- Scale tip
- NA
- Smaller bracts at base of bracts
- there is no smaller, outer cycle of bracts
- Style branch number
- there are no obvious branches on the style
- Swelling at base of flower head
- the peduncles are not swollen, or only slightly
- Width of flower head base
- 6–14 mm
-
Fruits or seeds
- Ovary beak length
- 0 mm
- Ovary length in developed fruit
- 2.5–3.5 mm
- Seed hair tuft color
- the pappus hairs are white or off-white
- Seed hair tuft details
- the pappus hairs are hooked or barbed
- Seed hair tuft length
- 5–8 mm
- Seed hair tuft tips
- the pappus hairs are slender
- Seed hairs uniform
- there are two distinct lengths of pappus hairs
- Seed tuft scale number
- 0
- Seed tuft type
- the pappus is made of very fine hairs or bristles
- Top of disk flower ovary
- NA
- Tuft or plume on fruit
- at least a part of the plume is made up of fine bristles
-
Glands or sap
- Leaf blade glands
- the leaf blades have no glandular (translucent) dots or scales
- Sap
- the sap is milky and opaque, and may be white or colored
-
Growth form
- Growth form
- the plant has one or more free-standing stems
- Plant lifespan
- the plant is annual, it lacks evidence of previous years' growth
- Spines on plant
- there are spines on the plant
- Underground organs
- there is a thickened taproot on the plant
-
Leaves
- Hairs on underside of leaf blade
- the underside of the leaf is not hairy, or has very few hairs
- Leaf arrangement
- alternate: there is one leaf per node along the stem
- Leaf blade base
-
- the leaf has no petiole
- the leaf has no petiole and at the base it clasps the stem, or goes all the way around the stem so the stem appears to pierce the leaf
- Leaf blade base shape
- the base of the leaf is cordate (heart-shaped) or sagittate (arrow-shaped)
- Leaf blade bloom
- there is a noticeable powdery or waxy bloom on the underside of the leaf
- Leaf blade edges
-
- the edge of the leaf blade has lobes, or it has both teeth and lobes
- the edge of the leaf blade has no teeth or lobes
- the edge of the leaf blade has teeth
- Leaf blade length
- 60–350 mm
- Leaf blade shape
-
- 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 obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
- the leaf blade is spatulate (spoon-shaped; narrow near the base, then suddenly widening to a rounded tip)
- Leaf blade surface colors
- there is no noticeable color variation on the upper surface of the leaf
- Leaf blade width
- 10–150 mm
- Leaf disposition
- the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem
- Leaf spines
- there are spines along the leaf edges
- Leaf stalk
- the leaves have no leaf stalks, but attach directly to the stem
- Leaf stalk length
- 0 mm
- Leaf tip extension
- NA
- Leaf type
- leaves are simple (lobed or unlobed but not separated into leaflets)
- Leaflet number
- 0
- Specific leaf type
- the leaf has a row of two or more lobes on each side of the central axis
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- man-made or disturbed habitats
- meadows or fields
-
Scent
- Plant odor
- the plant does not have much of an odor
-
Stem, shoot, branch
- Flowering stem cross-section
- the flowering stem is circular, or with lots of small angles
- Leaves on stem
- there is at least one full leaf above the base of the flowering stem
- Stem bloom
-
- the stem has a powdery or waxy film on it that can be rubbed away
- there is no powdery or waxy film on the stem
- Stem internode hair direction
- NA
- Stem internode hair length
- 0 mm
- Stem internode hair type
- the stem has no hairs between the nodes
- Stem internode hairs
-
- the stem has hairs between the nodes
- the stem has no hairs between the nodes
- Stem wings
- the stem does not have wings on it
Wetland status
Usually occurs in non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)
In New England
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)
From Flora Novae Angliae dichotomous key
3. Sonchus oleraceus L. E
common sow-thistle. CT, MA, ME, NH, RI, VT. Fields, roadsides, pastures, waste areas.
Native to North America?
No
Sometimes confused with
- Sonchus arvensis:
- flower heads 3-5 cm wide and plants perennial from a deep-seated rhizome (vs. S. oleraceus, with flower heads 1.5-2.5 cm wide and plants annual from a taproot). Sonchus asper: basal auricles of leaves rounded and stalks to flower heads with abundant stipitate glands (vs. basal auricles of leaves +/- triangular and stalks to flower heads without stipitate glands or these few and sparse).