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- All other flowering non-woody plants
- Daisies, goldenrods, and other aster family plants
- Lactuca biennis
Lactuca biennis — tall blue lettuce
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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.
Facts
Native Americans used a decoction of the roots of tall blue lettuce to treat pain, vomiting, diarrhea, and heart trouble.
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
- Leaf type
- leaves are simple (i.e., 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
-
- blue to purple
- white
- yellow
- Tuft or plume on fruit
- at least a part of the plume is made up of fine bristles
- Spines on plant
- the plant has no spines
- Leaf blade length
- 100–400 mm
- Disk flower number
- 0
-
Flowers
- Bases of bract appendages
- NA
- 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 head shape
- the sides of the flower head are roughly parallel, like a cylinder
- 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
- 7–12 mm
- Inflorescence branching (Solidago)
- NA
- Inflorescence shape
- the inflorescence is not flat-topped but appears rounded, with some flower heads distinctly higher than others
- Ovary beak
-
- there is a beak on the ovary
- 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 roughly elliptical (widest in the middle, tapering to both ends)
- Ray flower color
-
- blue to purple
- white
- yellow
- Ray flower reproductive parts
- the ray flowers have both carpels and stamens
- Ray flowers
-
- 11-15
- 16-25
- 26-50
- 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 a disk-shaped platform above the ovary
- Scale tip
- NA
- Smaller bracts at base of bracts
- there is a cycle of much smaller bracts outside the cycle of larger and longer bracts
- Style branch number
- there are no obvious branches on the style
- Width of flower head base
- 5–8 mm
-
Fruits or seeds
- Ovary beak length
- 0–0.5 mm
- Ovary length in developed fruit
- 4–5 mm
- Ovary width in developed fruit
- 1.5–1.8 mm
- Seed hair tuft color
- the pappus hairs are tan to dark brown
- Seed hair tuft length
- 4–6 mm
- Seed hair tuft tips
- the pappus hairs are slender
- 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
- the plant is biennial, it appears as either first year (non-reproductive) plants or second year plants with flowers or fruit
- Spines on plant
- the plant has no spines
- Underground organs
- there is a thickened taproot on the plant
-
Leaves
- Hairs on underside of leaf blade
-
- the underside of the leaf is fuzzy or hairy
- 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 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 blade is cuneate (wedge-shaped, tapers to the base with relatively straight, converging edges), or narrow
- the base of the leaf is cordate (heart-shaped) or sagittate (arrow-shaped)
- Leaf blade bloom
-
- the underside of the leaf has no noticeable 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
- 100–400 mm
- Leaf blade shape
-
- the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
- the leaf blade is oblanceolate (lance-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
- there is no noticeable color variation on the upper surface of the leaf
- Leaf blade tip
- the tip of the leaf blade is acuminate (tapers to a long, thin point)
- Leaf blade width
- 40–200 mm
- Leaf disposition
- the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem
- Leaf spines
- there are no spines on 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 (i.e., 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
-
- edges of forests
- 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 length
- At least 0 mm
- 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
Occurs in wetlands or non-wetlands. (Wetland indicator code: FAC)
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
- widespread (S-rank: S5)
Native to North America?
Yes and no (some introduced)
Sometimes confused with
- Lactuca canadensis:
- flowers usually yellow and mature ovary with a slender, elongate beak 1-6 mm long (vs. L. biennis, with flowers usually blue and mature ovary beakless or with a short, stout beak 0.1-0.5 mm long).
Synonyms
- Lactuca spicata (Lam.) A.S. Hitchc. var. integrifolia (Torr. & Gray) Britt.
- Mulgedium spicatum (Lam.) Small var. integrifolium (Torr. & Gray) Small
- Sonchus biennis Moench
Family
Genus
From the dichotomous key of Flora Novae Angliae
1. Lactuca biennis (Moench) Fern. N
tall blue lettuce. Lactuca spicata (Lam.) A.S. Hitchc. var. integrifolia (Torr. & Gray) Britt.; Mulgedium spicatum (Lam.) Small var. integrifolium (Torr. & Gray) Small; Sonchus biennis Moench • CT, MA, ME, NH, RI, VT. Fields, roadsides, forest edges and clearing
1×2. Lactuca biennis × Lactuca canadensis → Lactuca ×morssii B. L. Robins. is a rare lettuce hybrid known from MA, ME. It is intermediate between the parental taxa or sometimes combines characteristics. It usually has blue ray flowers and off-white pappus bristles, the cypsela bodies intermediate or as in each parent (see key for differences in beak length and nerving of faces).