Don't know whether it helps or not, but the leaves taste a bit like rocket. The plants on Radio Hill were pretty much all beside the vehicle access track. They (or similar plants) seem to be fairly frequent in the Cooma area, along roadsides and as backyard weeds. I have assumed that some in my backyard are either from rocket or from Asian greens grown by neighbours. I removed one a few days ago that was in its second year, it had a long thin taproot.