Lysimachia punctata.

I have some of these and I am always digging them up as well never knew their name untill now Spritz just called them those yellow flowers

This is one plant I did not bring from my old garden. I was so fed up with trying to control it that I decided to leave it behind,

I don't blame you! It's pretty - but hard to keep digging it up. Not a well-behaved plant.

Pretty. I'd like to have one. What about in a container on a deck or something, to keep down the spreading.

Some plants are all about addition....other's like this ..it's subtraction!!
garden arithmetic? lol. I have a lysimachia with purple foliage and yellow flowers that came through the fence from a neighbour...she also sent me some raspeberry canes... so I planted aegopodium and spearmint on my side...hope she likes them!! lol. Whoever said "Good fences make good neighbours" never had her on the otherside of the fence!.