22 February 2012	22 February 2012	16 February 2012
C. texana	C. carduacea
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Central Texas Chaptalia: C. texana & C. carduacea

by Bob Harms 

I have long been familiar with the nodding closed heads of C. carduacea in the hill country west of Austin, Texas, in N. Hays County, but in mid March of 2010 I came across a population in Austin, Travis County, with an erect open head with prominent ray-like ligulate florets, a new species for me, C. texana. Recent taxonomic literature has treated C. carduacea Greene as a synonym of C. texana Greene, but detailed study of these two populations shows that they represent distinct species. Since, in spite of their differences, they have been merged into a single species, the Texas Chaptalia literature does not adequately account for either of them.