It is regarded as an invasive weed in many places, including New Zealand, and is more common here on roadsides and in waste areas. Its high-volume seed production means it can reproduce hastily. Seeds are carried for some distance on wind currents and are often found stuck to footwear or unintentionally transported by animals and wildlife.
It starts off as a rosette similar to weeds such as Hawksbeard and Shepherd’s Purse. It then sprouts tall upright stems, which branch near the top and produce large numbers of small seed-heads that are like dandelions. During the rosette stage, it can be identified against similar species as it doesn’t have lobes.
Herbicides containing a mixture of Triclopyr and Picloram (Victory Gold, Triumph Gold, Tordon Gold or Conquest) will provide good control. When the plants are younger, herbicides containing 2,4-D (2,4-Dichlorophenoxyacetic acid) are also effective.