A friend told me that when you've finally killed the last weed in your garden, you say "Oxalis all gone". It does seem to be the toughest weed for me to control. Fortunately it seems the iris aren't overly bothered by it. I used Preen in my sdb bed last year and didn't notice oxalis to be a problem. I had just taken that bed out of lawn though so I may be in for more problems this year.

I use a bamboo plant stake to loosen the type with a "nut". I'm finally, after 5 years, getting rid of it.

Thankfully I don't have nut grass here. But do have bindweed!

Thanks! I did search the other forums for oxalis and what I found was not encouraging.

There does seem to be one chemical that is narrow in scope, not too toxic, and works on oxalis, called "chickweed-be-gone." But I think I'll find out more about it first. Wouldn't want to find that it is like Round-Up and turns all your iris white!

Meanwhile, I'll keep pulling. I have screwdriver-like weeding tool to get the whole fleshy root, but I'm always worried about slicing the iris roots.