Sonchus asper (L.) Hill

Spiny-leaved sow-thistle, spiny sowthistle, prickly sowthistle, spiny-leaved sow thistle

About plant names...

Although native to Europe, spiny-leaved sow-thistle is a common weed in North America. It is also widespread in Africa, Asia, and Madagascar. In many habitats it is considered a nuisance, and in some it is an invasive.

Identification: Plants reach 3' (1 m) in height. Leaves are up to 6" (15 cm) long, and produce a milky sap when cut. Lower leaves are obovate or spatulate. Upper leaves become more oval or narrow in shape. Leaf edges are spiny, and attached directly to the stem. Clusters of yellow flowers, each ½-1" (1.3-2.5 cm) in diameter, appear at stem tips, appearing from May to October. Fruits are brown and wrinkly, about ⅛" (4 mm) around. They are surrounded by a white puffball. The flowers and the puffballs are reminiscent of small dandelions.

Edibility: Handling plants can cause contact dermatitis for some people: burning or redness, or rashes similar to those from poison ivy. However, younger plants harvested before spines have formed are edible, with lettuce- or Swiss chard-like flavor. Older plants, though non-poisonous, become more bitter and must have the spines cut off. Recipes here. (Thanks to Arpi Szabo for pointing out that sow-thistle is in fact edible. Arpi is a Hungarian student of plant protection mastery writing from SAPIENTIA Hungarian University of Transylvania, in Tîrgu-Mureș, Romania.)

Online References:

Missouriplants.com

The Virginia Tech Weed Identification Guide

EFloras

Illinois Wildflowers

CalPhotos

The Vanderbilt University Bioimages web site

in Flora of Zimbabwe

SEINet—the Southwest Environmental Information Network

6/30/2010 · Nashua River Rail Trail, Groton Center, Groton, Mass­a­chu­setts
≈ 10 × 7" (24 × 17 cm) ID is uncertain

6/30/2010 · Nashua River Rail Trail, Groton Center, Groton, Mass­a­chu­setts
≈ 4½ × 3½" (11 × 9.2 cm) ID is uncertain

10/6/2011 · Shieling Forest, Peterborough, New Hamp­shire
≈ 4 × 4" (10 × 10 cm) ID is uncertain

8/3/2009 · 111 Near 119, Pepperell, Mass­a­chu­setts
≈ 4½ × 3½" (11 × 8.9 cm) ID is uncertain

8/3/2009 · 111 Near 119, Pepperell, Mass­a­chu­setts
≈ 33 × 38" (82 × 95 cm) ID is uncertain

7/27/2010 · Nashua River Rail Trail, Groton Center, Groton, Mass­a­chu­setts
≈ 6 × 6" (14 × 14 cm)

7/17/2009 · Mt. Lebanon St, Trail, Pepperell, Mass­a­chu­setts
≈ 2 × 2" (5.2 × 5.7 cm)

5/22/2005 · Memphis, Ten­nes­see · By Tim Chandler ID is uncertain

10/6/2011 · Shieling Forest, Peterborough, New Hamp­shire
≈ 15 × 10" (39 × 26 cm) ID is uncertain

Sonchus asper description by Thomas H. Kent, last updated 21 Aug 2020.

© FloraFinder.org. All rights reserved.

7/11/2010 · Nashua River Rail Trail, Groton Center, Groton, Mass­a­chu­setts
≈ 6 × 4" (15 × 10 cm)

8/3/2009 · 111 Near 119, Pepperell, Mass­a­chu­setts
≈ 3 × 3½" (8.4 × 9.4 cm) ID is uncertain

6/30/2010 · Nashua River Rail Trail, Groton Center, Groton, Mass­a­chu­setts
≈ 7 × 4½" (17 × 11 cm) ID is uncertain

7/18/2020 · Woodward Point Preserve, Brunswick, Maine
≈ 4½ × 7" (12 × 18 cm)

2/24/2010 · Batiquitos Lagoon, Carlsbad, Cali­fornia
≈ 27 × 24" (68 × 60 cm)

7/17/2009 · Mt. Lebanon St, Trail, Pepperell, Mass­a­chu­setts
≈ 11 × 7" (28 × 18 cm)

7/18/2020 · Woodward Point Preserve, Brunswick, Maine
≈ 6 × 5" (16 × 13 cm)

2/24/2010 · Batiquitos Lagoon, Carlsbad, Cali­fornia
≈ 9 × 7" (22 × 18 cm)

8/3/2009 · 111 Near 119, Pepperell, Mass­a­chu­setts
≈ 3 × 2' (1 × 0.7 m) ID is uncertain

7/11/2010 · Nashua River Rail Trail, Groton Center, Groton, Mass­a­chu­setts
≈ 5 × 3½" (13 × 9.2 cm)

2/24/2010 · Batiquitos Lagoon, Carlsbad, Cali­fornia
≈ 9 × 9" (23 × 22 cm)

Range:

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