Note that at higher altitudes, this could be the native dandelion, Taraxacum aristum.
Environmental weed in NSW and Vic (as Taraxacum officinale).
http://keyserver.lucidcentral.org/weeds/data/media/Html/taraxacum_officinale.htm
Taraxacum sp. is listed in the following regions:
Canberra & Southern Tablelands | Southern Highlands | Albury, Wodonga | South Coast
Synonyms
Taraxacum officinale