WILD TURNIP
(Brassica tournefortii)
(Photos: E. Cousins, plant at Cape Jervis; http://swbiodiversity.org/seinet/imagelib/imgdetails.php?imgid=216484)
We’ve noticed a lot more of this weed around in the past couple of years: clumps seem to spring up, rather than just single plants, possibly where a seed head has blown in. The weed has a rosette of large leaves at ground level. As can be seen in the left hand picture above, the leaves are pretty hairy, and have lots of lobes. The flower stem towers over this base, up to about the level of your thigh. The flowers are a fairly ordinary yellow with four petals, and occur in winter to early summer. Having come from the desert areas of the Middle East, this plant knows how to survive in our drying soils in spring: it hogs the water in the soil, then sets seed earlier than most other plants. These seeds can survive for many years in the soil, and remain viable after droughts and bushfires. So the weed is hard to eradicate by just pulling out, or burning. Keep an eye out for infestations starting on roadsides, or sandy areas, and stop it early!