Common name: Indian Weed
Sigesbeckia orientalis L. APNI*
Synonyms: Sigesbeckia orientalis L. subsp. orientalis APNI*
Description: Erect herb to 80 cm high; stems slightly pubescent, brown.
Leaves lanceolate to spear-shaped, 2–15 cm long, 1–7 cm wide, in remote pairs, petiolate, pubescent, with glandular hairs, veins prominent.
Heads 10 mm diam.; outer involucral bracts irregular, spreading, narrow-spathulate, 7–11 mm long, densely covered with dark stalked glands. Ray florets c. 8, ligules 1–2 mm long, broad-oblong, 2- or 3-toothed at apex, yellow. Disc florets 10–15, yellow.
Achenes 2–3 mm long, slightly angled, black.
Distribution and occurrence: Grows in soils ranging from shallow stony to grey soils of river banks, west to Cobar district, also native to Asia and Africa.
NSW subdivisions: NC, CC, SC, NT, CT, ST, CWS, NWP, SWP
Other Australian states: Qld Vic. Tas. N.T. S.A. W.A.
There is debate about this species being native or introduced. See Bean, A.R.(2007) Australian Systematic Botany 20, 1-43, in particular page 20. Updated L. Murray (September 2011). NSW Herbarium treats this species as native.
Text by L. Murray
APNI* Provides a link to the Australian Plant Name Index (hosted by the Australian National Botanic Gardens) for comprehensive bibliographic data
***The AVH map option provides a detailed interactive Australia wide distribution map drawn from collections held by all major Australian herbaria participating in the Australian Virtual Herbarium project.