Mystery plant in Alpine trough.

Can anyone identify the yellow plant that I've noticed in one of our Alpine troughs? I cannot remember planting it. The leaves are like a four leaf clover, & very small. Sorry about the pigeon feather, I used it to keep the stem upright to take a photo!

 

Sorry, forgot to upload photo!

 

Oxalis cornuta and a right thug it is too.

 

Many thanks. I'll keep an eye on it as we're plagued by the brown-leaved species.

 

Or even Oxalis corniculata......as Palustris says...."and a right thug it is too."

Oxalis corniculata - Google Search

 

Sorry, my fingers missed the middle of the name.