Lactuca canadensis (wild lettuce)

Lactuca canadensis L.

Lactuca sagittifolia Elliott

Lactuca canadensis L. var. integrifolia (Bigelow) Torr. & A. Gray

Lactuca canadensis L. var. latifolia Kuntze

Lactuca canadensis L. var. longifolia (Michx.) Farw.

Lactuca canadensis L. var. obovata Wiegand

Lactuca canadensis L. var. typica Wiegand

Lactuca steelei Britton

Lactuca sagittifolia Elliot

Wild lettuce, Canada lettuce

Kingdom	Plantae	Plants, but not fungi, lichens, or algae
Subkingdom	Tracheobionta	Vascular plants—plants with a “circulatory system” for delivering water and nutrients
Division	Magnoliophyta	Flowering plants, also known as angiosperms
Class	Magnoliopsida	Dicotyledons—plants with two initial seed leaves
Subclass	Asteridae	A large class that encompasses asters
Order	Asterales	Flowering plants with a central disk flower and surrounding petals, like daisies
Family	Asteraceae	The aster family, which also includes daisies and sunflowers; from the Greek ἀστήρ, “star,” for the star-shaped flowers
Genus	Lactuca	From lacta, Latin for “milk,” referring to the milky sap in stem, and a root word for lactic acid
Species	canadensis	“Of or referring to Canada”

About plant names...

Wild lettuce is a widespread North American native.

Plants: 4-10' (1.2-3 m) tall, with stems that are green or spotted with purple. The latex from a broken stem is brown.

Leaves: Leaves vary greatly in shape, and may resemble the shape of a sickle, or be long and narrow, or have wider and deep lobes. They are 6-14" (15-35 cm) long.

Flowers: At the top, large cone-shaped panicles consisting of 50-100 flowers appear. Individual flowers are about ¼" (8.5 mm) around, with 15-22 florets (tiny petals) each. They are yellow, pinkish-orange, or reddish.

Fruits: The achenes (seeds) are small and brown, each with a “parachute” attached, like dandelions.

6/22/2010 · Nashua River Rail Trail, Ayer, MA
≈ 21 × 31" (52 × 78 cm)

6/15/2012 · Tom and Susan’s, Pepperell, MA
≈ 11 × 7" (27 × 18 cm)

7/15/2012 · Gordon and Kathy’s, Prospect, ME
≈ 12 × 17" (29 × 44 cm)

Some Lactuca species:

	*Lactuca biennis*	You are here Lactuca canadensis	*Lactuca serriola*
Common Name	tall blue lettuce	wild lettuce	prickly lettuce
Plant	Tall blue lettuce grows up to 6' (1.8 m) high.	4-10' (1.2-3 m) tall, with stems that are green or spotted with purple. The latex from a broken stem is brown.	Erect, 12-79" (30-200 cm) tall. Stems sometimes have stiff hairs near the bottom; stems and leaves have a milky sap when cut.
Flowers	Blue, about ¼-½" (6.3-12 mm) across, in crowded clusters at the top.	At the top, large cone-shaped panicles consisting of 50-100 flowers appear. Individual flowers are about ¼" (8.5 mm) around, with 15-22 florets (tiny petals) each. They are yellow, pinkish-orange, or reddish.	In panicles that form open, roughly conical clusters of flowers. Flowers are ⅜-½" (1-1.5 cm) in diameter, and have 13-27 florets (petals) each. Flowers appear July-September.
Leaves	Leaves are deeply divided, like those of dandelions, but while dandelion leaves are roughly the same width along their length, these are more triangular in overall shape. They are up to 12" (30 cm) long and 6" (15 cm) wide at the base, tapering to sharp tips. Leaves are hairy, undersides more so.	Vary greatly in shape, and may resemble the shape of a sickle, or long and narrow, or wider and deep lobes. They are 6-14" (15-35 cm) long.	Alternate, 1¾-12" (5-30 cm) long and ⅜-4" (1-10 cm) wide. The mid-ribs of leaves have prickers along the bottom. Typically leaves are deeply lobed.
Fruit		Achenes (seeds) are small and brown, each with a “parachute” attached, like dandelions.	⅛" (3 mm) long, single-seeded, lance-shaped, attached to a “parachute” like dandelions.
Range/ Zones
Habitats	Redwood forest, wetlands	Woodland margins, clearings, near the edges of water, roadsides, pastures.	Grasslands, seasonal wetlands, orchards, vineyards, urban places, roadsides, disturbed habitats.
Type	Wild	Wild	Wild
Occurrence	Common	Common	Common

Edibility: Leaves are edible when cooked, but not especially desirable.

Online References:

Lactuca canadensis on CalPhotos

Lactuca canadensis at Illinois Wildflowers

Lactuca canadensis on Kansas Wildflowers and Grasses

Lactuca canadensis on Wildflowers of the United States

Lactuca canadensis on Plants for a Future, a resource and information centre for edible and otherwise useful plants

Lactuca canadensis on Delaware Wildflowers

Lactuca canadensis on SEINet—the Southwest Environmental Information Network

Lactuca canadensis on eFloras

7/9/2012 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 13 × 19" (33 × 47 cm)

7/9/2012 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 8 × 5" (20 × 13 cm)

7/9/2010 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 12 × 17" (29 × 44 cm)

7/9/2012 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 4½ × 3" (11 × 7.9 cm)

7/9/2010 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 17 × 12" (44 × 29 cm)

6/26/2010 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 5 × 3½" (13 × 9.2 cm) ID is uncertain

9/13/2009 · Tom and Susan’s, Pepperell, MA
≈ 16 × 24" (41 × 62 cm) ID is uncertain

7/9/2012 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 3½ × 2½" (9.8 × 6.6 cm)

8/28/2012 · Tom and Susan’s, Pepperell, MA
≈ 4 × 6" (10 × 15 cm) ID is uncertain

9/13/2009 · Tom and Susan’s, Pepperell, MA
≈ 16 × 24" (41 × 62 cm) ID is uncertain

Lactuca canadensis description by Thomas H. Kent, last updated 16 Sep 2020.

8/28/2012 · Tom and Susan’s, Pepperell, MA
≈ 9 × 14" (23 × 35 cm) ID is uncertain

6/15/2012 · Tom and Susan’s, Pepperell, MA
≈ 4½ × 7" (11 × 17 cm)

8/28/2012 · Tom and Susan’s, Pepperell, MA
≈ 9 × 14" (23 × 35 cm) ID is uncertain

7/15/2012 · Gordon and Kathy’s, Prospect, ME
≈ 15 × 10" (39 × 26 cm)

6/26/2010 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 6 × 4" (15 × 10 cm) ID is uncertain

8/11/2010 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 7 × 4½" (17 × 11 cm) ID is uncertain

6/26/2010 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 12 × 17" (29 × 44 cm) ID is uncertain

7/9/2010 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 6 × 4" (15 × 10 cm)

6/22/2010 · Nashua River Rail Trail, Ayer, MA
≈ 21 × 31" (52 × 78 cm)

Range:

About this map...