Coreopsis

BUSH INVADER

Coreopsis lanceolata

family: ASTERACEAE (daisy family)

Description

  • Perennial herbaceous yellow daisy from North America, forming dense clumps up to 1m high and wide, dies down after seeding until the following spring. Also known as Calliopsis and Tickweed.
  • Leaves are light to mid green, hairy, and very variable. Lower leaves grow from the roots on long stems to form a rosette at ground level; they are lance shaped, or resemble an elongated spatula, and may be lobed. Upper leaves, growing from the stem, are often deeply lobed.
  • Flowers are golden yellow daisies with yellow centres, on long single stems. The 8 ray petals are toothed on the tips. Flowers over many months, profusely in summer.
  • Produces copious black flattened seeds 2-3mm long with 2 broad papery wings. Germination rates are high.
  • Has a short woody rhizome and fibrous roots.

Dispersal

Spreads by means of wind and water, the movement of contaminated soil, by seed-eating birds, and through garden waste dumping. It is also widely believed that some persons have deliberately collected and scattered the seed along railway lines and roadsides.

Impact on Bushland

Prefers open areas and full sun, and was initially confined to roadsides, railway embankments, disturbed areas, and bushland edges. However Coreopsis is now moving down stormwater drains and watercourses into good bushland, following the siltation left by urban runoff. Its dense clumping habit and rapid spread can crowd out native plants and seriously reduce the germination of native seed.

Distribution

Throughout the Blue Mountains, but more visible west of Bullaburra.

Alternative Planting

Native Plants
Local native Hibbertias, eg Hibbertia serpylifolia, H. monogyna
Yellow Buttons (Chrysocephalum apiculatum)
local Rock Daisies, eg Brachyscome angustifolia

Exotic alternatives
Yellow Marguerite daisies
Yellow Flag Iris (Iris pseudacorus)

Control

Crown, making sure to remove the woody rhizome.
Pull small seedlings from moist soil.
Extensive infestations can be sprayed if no valued plants are present. Do this when the first flowers appear, ensuring seeds will not be set.
Get advice from Council if Coreopsis is growing along watercourses, including drains - you may need a permit to spray.

Warrimoo: The rapid spread of Coreopsis threatens the integrity of intact bushland.
Warrimoo: The rapid spread of Coreopsis threatens the integrity of intact bushland.

Coreopsis is a familiar sight along roadsides and in drains.

Masses of yellow Coreopsis daisies are a familiar sight along our roads and railway embankments, street edges and drains.
The white flower is another weed, Ox-eye Daisy.

Flowers are golden yellow daisies with yellow centres and 8 toothed petals.

Flowers are golden yellow daisies with yellow centres and 8 toothed petals. Each plant produces numerous flowers over a long period.

Picture of Coreopsis.

Coreopsis forms dense clumps up to 1m high. The shape of the mid-green leaves is very variable.