>

Sonchus species [Asteraceae]

Click on the images below to see larger versions.

Scientific Name Sonchus asper USDA PLANTS Symbol SOAS
Common Name Spiny Sow-thistle ITIS Taxonomic Serial No. 38424
Family Asteraceae (Sunflower) SEINet
Reference
Click Here
Description Habitat: Most soils and habitats, often disturbed areas; native to Europe but found almost everywhere in North America.
Plant: Erect, coarse annual up to 4 ft. tall, sometimes taller; solitary stems branched above and full of latex.
Leaves: Alternate, clasping, incised (lower) to dentate (mid-stem and above) leaves with sharp spines at lobe tips, 3 to 8 inches long overall; becoming smaller and lanceolate-deltoid above.
Inflorescence: Solitary yellow flower heads resembling dandelions atop short leafless stalks; about 1-1/8 inches across; many rays but no disk florets.
Bloom Period: All year.
References: "Wildflowers of the Texas Hill Country" by Marshall Enquist and "Wildflowers of Texas" by Geyata Ajilvsgi.
BONAP Distribution Map

Texas Status:
Introduced
Scientific Name Sonchus oleraceus USDA PLANTS Symbol SOOL
Common Name Common Sow-thistle ITIS Taxonomic Serial No. 38427
Family Asteraceae (Sunflower) SEINet
Reference
Click Here
Description Habitat: Most soils and habitats, including cultivated gardens, streets, parking areas, and disturbed areas; native to Eurasia but found almost everywhere in North America; images below came from plants growing in sandy soil next to the Rio Grande in Big Bend.
Plant: Erect annual or biennial 4 inches to almost 5 ft. tall; solitary stems branched above near the inflorescence and full of latex.
Leaves: Lower leaves are pinnatifid with deep triangular lobes, dentate margins with soft prickles; upper are alternate, clasping and generally entire or with shallow lobes; upper surfaces dull green and hairless.
Inflorescence: Tight clusters of flower heads resembling dandelions at the top of the stem and arising from leaf axils, each 3/4 to 1-1/4 inches across; many yellow (or whitish) rays but no disk florets; blooming early in the day and closing by noon.
Bloom Period: All year.
References: SEINet, Illinois Wildflowers and Minnesota Wildflowers.
BONAP Distribution Map

Texas Status:
Introduced

© Tom Lebsack 2022