Coreopsis lanceolata L.
This is an upright annual or short-lived perennial (2-3 years). It grows in clumps up to 1 m high. The stems and leaves are covered in stiff long hairs.
Basal leaves are elongated and narrow on long slender stems, 4-30 cm long, 10-20 mm wide and lance to spoon shaped. The margin of the leaf is usually entire (smooth) but occasionally with 1 or 2 lobes at the base. Upper leaves have no stalk, however are borne on the elongated aerial portions of the stem and are variable in shape. The margins of the upper leaves are also entire (smooth).
Flowerheads are bright golden yellow, daisy-like, usually solitary (only 1 per stem but occassionally 2 or 3), with 8 petals and are on a long leafless stalk. Ray florets (petals) are markedly toothed at the ends. Flowers can be seen in Summer.
Fruit is an achene (dry, 1 seeded and opens when ripe). The seed is black with 2 papery, broad wings.
Other plants easily confused with this plant
This plant, before flowering, could be mistaken for a species of Plantago (Plantain) or perhaps Lobelia dentata or Lobelia gibbosa. Coreopsis has lobes at the base of the leaves and smooth margins, whereas Plantago and Lobelia have teeth along the leaf margins.
Sources & References
"Weeds - an illustrated botanical guide to weeds of Australia" by B. A. Auld and R. W. Medd
"Gardener's Companion to Weeds" by Suzanne Ermert and Leigh Clapp
"Plantnet FloraOnline" (2005) http://plantnet.rbgsyd.nsw.gov.au/
South Coast Weeds www.esc.nsw.gov.au/weeds
Prepared by Justin KY Chu, July 2005
Checked by IEWF, January 2006
Checked by Barbara Wiecek, Botanic Gardens Trust, Sydney, June 2006