woolly distaff thistle
(Carthamus creticus)
This species is Introduced in the United States
ORIGIN: Mediterranean
GROWTH TRAITS: An herbaceous winter annual growing upright to 3.2’ tall (1 m) from slender, fibrous taproots. Stems are straw-colored. Stems and leaves are covered in tiny glandular hairs. Stem leaves are alternate, stiff, weakly clasp the stem, and often spread backward. Leaves have lobes tipped with sharp spines. Basal leaves are larger than stem leaves and are typically absent at flowering. Flower heads appear solitary on stem tips in summer. Each capitulum has several rows of bracts and yellow florets. Outer bracts are stiff, leaf-like, and
spread backward; inner bracts are smaller, spiny, and less lobed. Seeds are brown achenes. Outer seeds are rough and lack pappus; inner seeds are smoother with stiff, persistent pappus. Hairs on stems, leaves, and flower heads are only slightly woolly. Seed pappus is 0.3-0.4” long (8-10 mm).
REPRODUCTION: Spread by seed only. Most seeds germinate within three years, though some may remain viable in the soil for eight.
HABITAT: Found in disturbed, open sites including agricultural fields (especially grain), grasslands, and pastures.
LOOK-ALIKES: Their spiny nature differentiates these species from nonthistle look-alikes. Most other thistles do not have yellow florets or stiff, thick, backward-spreading leaves. Golden thistle (Scolymus hispanicus) is most similar but has milky sap and winged stems.
CITATIONS:
Winston, R.L., Andreas, J.E., Milan, J., DesCamp, W., Randell, C.B., and M. Schwarzlander. 2014. New Invaders of the Southwest. United States Department of Agriculture, Forest Health Technology Enterprise Team. FHTET-2014-12. Retrieved from https://bugwoodcloud.org/resource/files/14767.pdf
Winston, R.L., Andreas, J.E., Milan, J., DesCamp, W., Randell, C.B., and M. Schwarzländer. 2014. New Invaders of the Northwest. United States Department of Agriculture, Forest Health Technology Enterprise Team. FHTET-2014-12. Retrieved from https://www.fs.fed.us/foresthealth/technology/pdfs/FHTET-2014-12_NW_New_Invaders.pdf
GROWTH TRAITS: An herbaceous winter annual growing upright to 3.2’ tall (1 m) from slender, fibrous taproots. Stems are straw-colored. Stems and leaves are covered in tiny glandular hairs. Stem leaves are alternate, stiff, weakly clasp the stem, and often spread backward. Leaves have lobes tipped with sharp spines. Basal leaves are larger than stem leaves and are typically absent at flowering. Flower heads appear solitary on stem tips in summer. Each capitulum has several rows of bracts and yellow florets. Outer bracts are stiff, leaf-like, and
spread backward; inner bracts are smaller, spiny, and less lobed. Seeds are brown achenes. Outer seeds are rough and lack pappus; inner seeds are smoother with stiff, persistent pappus. Hairs on stems, leaves, and flower heads are only slightly woolly. Seed pappus is 0.3-0.4” long (8-10 mm).
REPRODUCTION: Spread by seed only. Most seeds germinate within three years, though some may remain viable in the soil for eight.
HABITAT: Found in disturbed, open sites including agricultural fields (especially grain), grasslands, and pastures.
LOOK-ALIKES: Their spiny nature differentiates these species from nonthistle look-alikes. Most other thistles do not have yellow florets or stiff, thick, backward-spreading leaves. Golden thistle (Scolymus hispanicus) is most similar but has milky sap and winged stems.
CITATIONS:
Winston, R.L., Andreas, J.E., Milan, J., DesCamp, W., Randell, C.B., and M. Schwarzlander. 2014. New Invaders of the Southwest. United States Department of Agriculture, Forest Health Technology Enterprise Team. FHTET-2014-12. Retrieved from https://bugwoodcloud.org/resource/files/14767.pdf
Winston, R.L., Andreas, J.E., Milan, J., DesCamp, W., Randell, C.B., and M. Schwarzländer. 2014. New Invaders of the Northwest. United States Department of Agriculture, Forest Health Technology Enterprise Team. FHTET-2014-12. Retrieved from https://www.fs.fed.us/foresthealth/technology/pdfs/FHTET-2014-12_NW_New_Invaders.pdf
Maps
EDDMapS Distribution - This map is incomplete and is based only on current site and county level reports made by experts, herbaria, and literature. For more information, visit www.eddmaps.org
State Lists - This map identifies those states that have this species on their invasive species list or law.
Invasive Listing Sources
Taxonomic Rank
| Domain: Eukarya |
| Kingdom: Plantae |
| Phylum: Magnoliophyta |
| Class: Magnoliopsida |
| Superorder: Asteranae |
| Order: Asterales |
| Family: Asteraceae |
| Subfamily: Carduoideae |
| Tribe: Cardueae |
| Genus: Carthamus |
| Carthamus creticus |
References
Common Name Reference: The Plant List (2010). Version 1. Published on the Internet; http://www.theplantlist.org/ (accessed 1st January).
Scientific Name Reference: The Plant List (2010). Version 1. Published on the Internet; http://www.theplantlist.org/ (accessed 1st January).