I'm glad I asked Eric.
I have one very pretty white flower - Ive never positively identified it yet - inherited with this (my dads) house.
Possibly Scilla.
It started in a bed at the front. Now it has spread to the side, back - everywhere!
Problem is, it self seeds, and Ive observed by attempting to dig up the bulbs that the seedlings immediately develop a root shoot which dives straight underground. The bulbs are formed in Australia, and so numerous they are almost impossible to eradicate when in the wrong spot.
Are those rampant varieties of Allium something similar?