This small herb is very common around Campbells Creek, even persisting in lawns of introduced grasses. It is much smaller than the notorious 'Soursob' (Oxalis pes-caprae), it creeps along the ground, sets seed and doesn't have underground bulbs.
Read more about and see more of this plant at the Flora of Victoria web site.
Read more about and see more of this plant at the VicVeg Online web site.
Or find even more information about this plant at the Google web site.