A page for wildflower and hiking enthusiast. A lot of my pictures, both wildflowers and scenery, come from the beautiful Tennessee State Parks. I use the Lady Bird Johnson Wildflower Center for my description of native plants. All non-native plants will use someone else for the description. The best way to follow this blog is to enter your e-mail address below. You will receive an e-mail that looks just like the post with all the pictures.
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Saturday, June 9, 2012
Carolina Thistle (Cirsium carolinianum (Walt.) Fern. & Schub.)
Family - Asteraceae
Stems - Erect, to +1.2m tall, branching above, hollow, herbaceous, tomentose to hirsute below, arachnoid pubescent above, carinate, from weak roots.
Leaves - Alternate. Lowest leaves petiolate. Petioles to +15cm long. Blade to +20cm long, +3cm broad. Cauline leaves sessile, linear-oblong, weakly lobed, with spines on margins only, greatly reduced above, to 15cm long(below), +/-1.5cm broad.
Inflorescence - Loose paniculate or cymose arrangement of flower heads terminating stems. Peduncles arachnoid pubescent, long, naked. Each peduncle typically subtended by a small foliaceous bract. Bracts arachnoid pubescent and prickle-margined.
Involucre - To 2cm tall(long), +/-1.5 in diameter, viscous. Phyllaries imbricate, tightly appressed, with a conspicuous whitish gland on midrib, sparse arachnoid pubescent to very sparse pilose, each tipped by a long thin bristle (to +3.5mm long).
Ray flowers - Absent.
Disk flowers - Corolla rose-pink to pinkish-purple for most of length, whitish near base, to +/-2cm long, 5-lobed, glabrous. Lobes 3.5mm long, linear. Stamens 5. Anthers pinkish-purple, connate around style, typically exserted. Style rose-pink, well exserted, glabrous, 2.6cm long. Achenes (in flower) glabrous, white, 2mm long, angled. Pappus of white plumose bristles to 1.6cm long.
Photographic Location - Falls Creek Falls State Park TN.
Flowering - May - July.
Habitat - Rocky open woods, bluffs, ravines, valleys, thickets.
Origin - Native to U.S.
Other info. - This is an easy plant to ID in the field. The sticky phyllaries with their large whitish glands and long bristle tips are a dead give-away for the species, as well as the long, naked peduncles. It would make a good garden subject as it requires no care and has practically no spines compared to other members of the genus.
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