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.
Cauline leaves.
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).
Involucre of late season or deprived plant.
Involucre of healthy plant.
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.
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.
This species is only found in the southeast corner of Missouri. It would make a good garden subject as it requires no care and has practically no spines compared to other members of the genus.
Photographs taken CR 160-152, Mark Twain National Forest, Oregon County, MO., 7-14-00, and in Ellington, MO., 5-26-03.
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