The small tubers/bulbettes of this very invasive plant are easily spread by rototilling, digging, transplanting and even dividing other plants where the tubers are growing side by side. March is the time to attack--I've been trying to control this plant on two separate properties (mine) over 15 years. It can be greatly reduced and in some cases eliminated through persisitance. I carefully hand pull the enemy from my garden beds. I will admit to doing little with it in the lawn--if you could call my spring melange of ajuga, lesser celandine, naturalized bulbs a lawn. Lesser celandine is emphemeral and disappears in the heat at the end of May, so if you are going to continue to try and eradicate it, you have to mark where it is now...

The one side of our property line boarders a woodland area with a stream. The first spring after we moved into the house I discovered we had a yellow flower that grew all over the place. I later found out it was Lesser Celandine. I have tried to kill the invasive plant with Round-up but I am realizing that this would be a lifelong & very expensive battle since our property boarders the woods which is covered with a thick carpet of this stuff. Not to mention our neighbors do not do anything to try and erradicate the invasive plant. Wondering if there is any sort of ground barrier that I can put in the ground around my property (similar to what they do for bamboo) that would at least stop the majority of the spreading coming up from the woods. That way I erradicate what I currently have in my property and stop the spreading of new growth coming from the woods. Does anyone know if a ground barrier would work for a tubler/bulblet type plant? If so how deep would the ground barrier have to go and what type of barrier material should I use (galvanized sheetmetal, plastic, etc?) Thanks!

When growing in a planting bed, the easiest form of removal is to dig each clump out. Time consuming I know, but this is really the most effective way to remove all the tubers and bublets from which this plant grows and also its primary means of spreading. Since this is a spring ephemeral - disappears soon after flowering until reappearing early next spring - now is the time to do this, especially before any flowers have time to set seed. I had this in my old garden - actually the more desirable named forms like Brazen Hussy, Dusky Maiden and Damerham, but they all reverted to species. I was pretty diligent about weeding out extras and keeping it confined to a single area and so did't actually object to the plant too much since it disappeared pretty early in the season. But it is one of those plants you simply cannot ignore or it will spread vigorously into parts of the garden you do not want or worse, into wild or natural areas.

It is definitely lesser celandine. Removing the flowers won't help much since it spreads predominantly by tubercles rather than seed. You are very lucky it hasn't taken over your garden. It's all over mine, which incidentally is damp and clayey. It is ephemeral and will disappear come summer. As Carol says it's now Ficaria verna, not a Ranunculus.