Lactuca canadensis

This biennial plant is usually unbranched and 3-8' tall. The central stem is terete and glabrous, light green or reddish green (sometimes with purple streaks), and often glaucous. The alternate leaves are light green to dark green, sometimes with purple edges or a yellowish cast. They are up to 10" long, 3" across, and lanceolate-oblong in shape. The largest leaves have deep pinnate lobes, while the smaller leaves have shallow pinnate lobes or none; they are wider at their bases than at their tips, and their bases clasp the stem. Occasionally, the leaves have widely spaced small teeth along their margins and short fine hairs along the underside of their central veins. The leaf surface can be shiny or dull.  The small dandelion-like flowerheads occur in a narrow panicle up to 2' long at the apex of the plant. The petaloid rays of the florets are yellow or slightly reddish orange. Each flowerhead is about 1/3" (8 mm.) across, consisting of 12-25 ray florets. Around the base of each flowerhead, there are several floral bracts (phyllaries) in several series that are appressed together and vary in size. These bracts are light green and glabrous; sometimes they are tinted purple or red. The blooming period occurs during late summer or early fall, lasting about 3-4 weeks. There is no noticeable floral scent. The flowers are replaced by dark brown achenes with tufts of white hair, which are attached together by thread-like beaks. Each achene has a central longitudinal ridge with some black splotches on either side; they are ovoid, flattened in shape, and slightly curved. The length of the achenes is equal to, or greater than, the length of their attached beaks. The inflorescence often has buds, flowers, and achenes existing together in different stages of development. The achenes are distributed by the wind. The root system consists of a thick deep taproot. There is a white latex in the root, leaves, and stems. Cultivation

This is a common and weedy plant with a highly variable appearance. It resembles the non-native Lactuca serriola (Prickly Lettuce), however the latter has gray achenes that are always shorter than the thread-like beaks that attach them to tufts of hair. Also, the leaves of Prickly Lettuce tend to be more blue in appearance, and they have stout prickly hairs along the central veins on the underside of their leaves. Wild Lettuce can be distinguished from other native Lactuca spp. by the color of its flowers, the appearance of its achenes with attached tufts of hairs, and the absence of hairs on its stems and leaves (aside from the scattered non-prickly hairs that may appear along the central veins on the underside of the leaves). Return

The native Wild Lettuce is a common plant that occurs in almost all counties of Illinois (see Distribution Map). Habitats include moist to slightly dry black soil prairies, clay prairies, gravel prairies, openings in woodlands, thickets, savannas, lake borders and riverbanks, limestone glades, fence rows, pastures and abandoned fields, powerline clearances, areas along railroads and roadsides, vacant lots, and miscellaneous waste areas. This plant is more common in degraded prairies and disturbed habitats, although it can also be found in high-quality habitats. Faunal Associations

Lactuca sagittifolia Elliott:
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Lactuca canadensis fo. canadensis :
Canada (North America)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Lactuca canadensis var. obovata Wiegand:
Canada (North America)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Lactuca canadensis var. canadensis :
Canada (North America)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Lactuca canadensis var. longifolia (Michx.) Farw.:
Canada (North America)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Lactuca canadensis var. latifolia Kuntze:
Canada (North America)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Lactuca canadensis L.:
Canada (North America)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Biennials, (15–)40–200(–450+) cm. Leaves on proximal ¹/2–³/4 of each stem; blades of undivided cauline leaves oblong, obovate, or lanceolate to spatulate or lance-linear, margins entire or denticulate, midribs sometimes sparsely pilose. Heads in ± corymbiform to paniculiform arrays. Involucres 10–12+ mm. Phyllaries usually reflexed in fruit. Florets 15–20+; corollas bluish or yellowish, usually deliquescent. Cypselae: bodies brown (often mottled), ± flattened, elliptic, 5–6 mm, beaks ± filiform, 1–3 mm, faces 1(–3)-nerved; pappi white, 5–6 mm. 2n = 34.

Lactuca canadensis var. latifolia Kuntze; L. canadensis var. longifolia (Michaux) Farwell; L. canadensis var. obovata Wiegand; L. sagittifolia Elliott

The native Wild Lettuce is a common plant that occurs in almost all counties of Illinois (see Distribution Map). Habitats include moist to slightly dry black soil prairies, clay prairies, gravel prairies, openings in woodlands, thickets, savannas, lake borders and riverbanks, limestone glades, fence rows, pastures and abandoned fields, powerline clearances, areas along railroads and roadsides, vacant lots, and miscellaneous waste areas. This plant is more common in degraded prairies and disturbed habitats, although it can also be found in high-quality habitats. Faunal Associations

Latuca canadensis (Wild Lettuce)
(Bees collect pollen or suck nectar; observations are from Robertson and Estes & Thorp)

Bees (long-tongued)
Megachilidae (Megachilini): Megachile latimanus sn cp (Rb)

Bees (short-tongued)
Halictidae (Halictinae): Lasioglossum lustrans sn (ET)

The following is a representative barcode sequence, the centroid of all available sequences for this species.

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 5
Specimens with Barcodes: 13
Species With Barcodes: 1

Rounded Global Status Rank: G5 - Secure

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: N5 - Secure