Weedy notes: capeweed
BOTANIC NAME
Arctotheca calendula
FAMILY
Asteraceae
GROWTH FORM
- annual
- stemless or short-stemmed herb to 30cm high, 80cm wide growing in rosette shape
- grows as whorl of leaves close to the ground
- leaves 5–25cm long, 2–6cm wide on 6cm stalks
- taproot
- flowers — 1.5–2.5mm long yellow daisy-like petals to 15mm diameter radiating from central dark core; undersides whitish and covered by thick mat of short hairs
- dies off in late summer.
CENTRE OF DIVERSITY
South Africa
HABITAT
Naturalised in Australia. A widespread and common weed of lawns, pastures and unused land. Occurs throughout Tasmania, particularly on light sandy soils.
REPRODUCTION
- from seed
- germinates in autumn with seedlings appearing late February-late April
- spread by animals, wind, water and in hay.
USES
- reported to be nutritious to stock (see caution below)
- provides habitat for the beneficial insects that target Lepidoptera (https://www.awri.com.au/industry_support/viticulture/weed-management/weeds/capeweed/).
CAUTION
- grazing of young, rapidly growing plants can cause nitrate poisoning
- high intake by dairy cattle can taint milk
- may cause nitrogen poisoning in other livestock.
MANAGEMENT
Avoid bare soil patches in late summer and autumn as these can be colonised by capeweed.
Hand removal: taprooted; use a garden fork — capeweed can be difficult to pull by hand; loosen soil around the plant and then lift, removing as much of the root system as possible.
Large infestations/farmland: cultivate and sow to pasture, crops or cover crops to eradicate large infestations; expose the root systems with minimal breakage and leave the plants to dry out and die.
- eradicate before the plants reach the flowering stage
- control becomes difficult once plants reach seeding stage of life cycle
- chipping has limited effect on recurrence as regrowth takes place from roots remnants left in the soil.
STATUS
Not a declared weed in Tasmania.
NOTES
- in the home garden capeweed competes with herbaceous and lawn plants, and on farmland with pasture grass and clover
- capeweed does not compete well in natural undisturbed ecosystems; a relatively poor competitor with native species.
SOURCES/MORE INFORMATION
Tasmania:
https://nre.tas.gov.au/invasive-species/weeds/weeds-index/non-declared-weeds-index/capeweed
Victoria:
https://vro.agriculture.vic.gov.au/dpi/vro/vrosite.nsf/pages/sip_capeweed
Other:
https://www.awri.com.au/industry_support/viticulture/weed-management/weeds/capeweed/