Texas Thistle

Cirsium texensis
TEXAS THISTLE
Cirsium texensis
Did you know that this photo shows over 100 individual flowers?

The structures that most people consider flowers in the sunflower family are dense clusters of flowers.

These specialized structures are called flowering heads (also known as capitula). Instead of pumping a bunch of energy into making one flower showy, Texas thistle (like other members of the family) put their energy into producing a lot of little flowers. Instead of keeping these flowers spread out, the plants have evolved to pack them all together in a single showy package. As one of the most widespread and diverse plant families on earth, this strategy has been proven quite effective!

More From Wikipedia

Cirsium texanum
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Order: Asterales
Family: Asteraceae
Genus: Cirsium
Species:
C. texanum
Binomial name
Cirsium texanum
Synonyms[1]
  • Carduus austrinus Small
  • Carduus filipendulus (A.Gray) Rydb.
  • Carduus helleri Small
  • Cirsium austrinum (Small) E.D.Schulz
  • Cirsium helleri (Small) Cory

Cirsium texanum is a species of plant in the tribe Cardueae within the family Asteraceae found in North America. Common names include Texas thistle, Texas purple thistle or southern thistle.[2] The species is native to northern Mexico (Coahuila, Durango, Nuevo León, San Luis Potosí, Tamaulipas) and the southern Great Plains of the south-central United States (primarily Texas, Oklahoma, and eastern New Mexico with additional populations in Louisiana, Arkansas, and Missouri).[3][4] It grows in prairies and roadsides.[5]

Cirsium texanum is a biennial or perennial herb up to 80 cm (32 inches) tall. Leaves have small, narrow spines along the edges. Flower heads are sometimes produced one at a time, sometimes in small groups, each head with light purple disc florets but no ray florets.[2]

The flowers of Cirsium texanum provide nectar for butterflies and the foliage is used as a source of food for the larvae of the painted lady butterfly. Goldfinches also use the seeds as a food source.[5]

References

  1. ^ The Plant List, Cirsium texanum Buckley
  2. ^ a b "Cirsium texanum in Flora of North America @ efloras.org". www.efloras.org. Retrieved 2024-03-08.
  3. ^ Biota of North America Program 2014 county distribution map
  4. ^ CONABIO. 2009. Catálogo taxonómico de especies de México. 1. In Capital Nat. México. CONABIO, México D.F.
  5. ^ a b "Lady Bird Johnson Wildflower Center - The University of Texas at Austin". www.wildflower.org. Retrieved 2024-03-08.