Chloracantha

Chloracantha is a monotypic genus of flowering plants in the aster family, containing the single species Chloracantha spinosa. It is distributed in the southwestern and south-central United States (CA NV AZ UT NM TX OK LA), most of Mexico, and much of Central America. Its English language common names include spiny chloracantha, spiny aster, devilweed aster, and Mexican devilweed. In Spanish it is known as espina de agua, espinaza, and espinosilla. This species is a perennial herb or subshrub; its green stems look more herbaceous than woody, "but it behaves more like a subshrub", with its tough stems living for several years and rapidly developing vascular cambia. The stems are hairless and sometimes waxy in texture, and some of the lateral branches may be sharply angled and reduced in size, becoming thorns. The alternately arranged leaves persist for only a short time and then fall away. Large colonies of these bare stems proliferate from a robust rhizomes. The stems usually reach a m......read more on Wikipedia.