Hi Frecko this is a new recorded location for this weed and there aren't that many from out your way. This could be because of low reporting but if it is uncommon out your way I strongly suggest that you get rid of it. I have removed many thousands from my sons block on Kangaroo Island and find that a mattock and gloved hand ensuring I have got all corms is the most effective way to get rid of it.
Thanks for that. I have to say that this is the only one I have ever seen in 29 years here (and it has been there for most of that time) and now, it seems, its time has come...