Adenocaulon

Hooker

Bot. Misc. 1: 19, plate 15. 1829.

Etymology: Greek aden, gland, and kaulos, stem
Treatment appears in FNA Volume 19. Treatment on page 77. Mentioned on page 12, 52, 70, 71, 78.

Perennials (perhaps flowering first-year, usually rhizomatous), (10–) 30–60 (–100+) cm (aerial stems usually proximally tomentose and distally stipitate-glandular). Leaves basal and cauline; petiolate (proximal) or sessile (distal); blades ovate to ± triangular [suborbiculate], bases mostly truncate to cordate or hastate, margins coarsely dentate or lobulate to denticulate or entire, abaxial faces tomentose, adaxial faces glabrate (distalmost leaves often linear or scalelike). Heads disciform, borne in open paniculiform arrays. Involucres cuplike to saucer-shaped (inconspicuous), 4–8+ mm diam. Phyllaries in 1–2 series, ovate to oblong, ± equal (reflexed in fruit), apices obtuse. Receptacles convex, smooth, glabrous, epaleate. Florets: outer 3–7 florets pistillate, corollas white or ochroleucous, obscurely zygomorphic (± 2-lipped; staminodes 4–5, minute; style-branches relatively short); inner 2–10 florets functionally staminate, corollas white or ochroleucous, actinomorphic (lobes 5); anther basal appendages (relatively short) entire, apical appendages narrowly triangular; style-branches none (apices of styles obtuse to acute). Cypselae clavate to obovoid, not beaked, ± ribbed, faces distally stipitate-glandular; pappi 0. x = 23.

Distribution

North America, Central America, s South America, e Asia

Discussion

Species 5 (1 in the flora).

Adenocaulon is well adapted for animal dispersal. The prominent glandular hairs on the cypselae are very sticky and cling readily to fabrics, fur, and feathers. The intercontinental disjunctions within the range of Adenocaulon are probably a result of dispersal of cypselae on the feathers of birds. Bird dispersal may also account for the intracontinental disjunctions of A. bicolor (in the Pacific Northwest, the Black Hills, and the northern Great Lakes region). An alternate hypothesis for the disjunctions of A. bicolor is a former transcontinental periglacial distribution that was broken apart by Holocene climatic changes.

... more about "Adenocaulon"
scarious +
paniculiform +  and open +
indeterminate +  and determinate +
David J. Keil +
Hooker +
mostly truncate +  and cordate or hastate +
compound +  and simple +
ovate;more or less triangular +
ribbed;smooth +
barbellulate +  and smooth +
actinomorphic +  and zygomorphic +
ochroleucous +  and white +
ribbed +  and not beaked +
clavate +  and obovoid +
North America +, Central America +, s South America +  and e Asia +
Greek aden, gland, and kaulos, stem +
stipitate-glandular +
staminate +  and pistillate +
fertile +  and bisexual +
winged +  and beaked +
dispersed +
in corymbiform , paniculiform or racemiform , arrays +  and singly +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
0.4 cm4 mm <br />0.004 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
cuplike;saucer-shaped +
sessile +  and petiolate +
cauline +  and basal +
lobulate +  and denticulate or entire +
2-carpellate +
persistent +
connate +  and distinct +
unequal +  and subequal +
bittmann1990a +  and bittmann1990b +
barbellulate +  and smooth +
plumose +, subulate +  and setiform +
exalbuminous +
prostrate +  and ascending +
appendaged +  and truncate +
hairy +  and glabrous +
papillate +
Compositae +
Adenocaulon +
Asteraceae tribe Mutisieae +
60 cm600 mm <br />0.6 m <br /> (100 cm1,000 mm <br />1 m <br />) +
30 cm300 mm <br />0.3 m <br /> (60 cm600 mm <br />0.6 m <br />) +
shrub +  and subshrub +