I don't even know its real name; when we were kids we used to call it "sour grass" and would chew on the sour leaves. Now I have other names for it, none that I can repeat here, as it invades my gardens seemingly overnight. It is everywhere, some small some much larger...gives new meaning ( or perhaps not) to the word pervasive.
I will be participating in Kathy's recipe swap on June 30...easy summer recipes! Come and join the fun on the 30th. Click the button on my sidebar for more info.
Further research tells me that Little Miss Anonymous is correct ( she always was so very smart) and it is called oxalis euraepa or yellow wood sorrel aka sourgrass. Okay to add to salads, but shouldn't be eaten in large quantities due to the oxalic acid content. Curious minds wanted to know;)