Sources that come up just doing a preliminary web search are all foreign.

I haven't even found any foreign ones. Please cite one to get me started.

I have a small patch of Oxalis and have no idea of the variety. It's under a group of Thuja plicatas and is just barely surviving. I've been meaning to put it in a better place, but I'm worried about it's aggressiveness. Guess I'll pot some up and see how it does.
Ozmirage, you're welcome to some whenever you want.
Mike...near Maple Valley

Thanks for your input, Mike. Here's a closeup of one of the individual plants. The pale lavender veins of the flowers are distinctive. The pic is two to three times life-size:

The trefoils of this species are smaller than most cultivated oxales, and the growth pattern more open, with single plants about saucer- to salad-plate size which propagate by wiry surface "roots" six or more inches long. The ones I've seen locally grow beautifully in full northern shade.

That's a new one on me! Since the Internet, it happens quite frequently. ;-)
Mike

Search oxalis acetosella price and the like.

Thanks, Embothrium, but all I get are other species and photo prints.

If you have seen them grown locally, bake up a batch of cookies and see if they would be willing to trade you a couple of starts for some home-baked goods :-)

Otherwise, it makes sense to consider the native species as a substitute. By just comparing photos - not ideal I realize - they look remarkably similar in appearance. And Oxalis oregana is easy to get your hands on.

You'd think so, wouldn't you, Gardengal? But what happened was that when I made my pitch (the sweetener in my case was a pot of home-made Sicilian blood-orange marmalade), the reaction was to totally stiff me.

There is no doubt that what you have seen here is this species and not another? The Plant Locator - Western Region (2004, Black-Eyed Susans/Timber) does say it was listed by the preceding version The Pacific Northwest Plant Locator. So stock was offered somewhere in the region under the name at one time.

There is always doubt about identifying species in a genus boasting more than 900, but I have looked at dozens of pictures, read dozens of descriptions, and consulted several experts, and so far everyone agrees (cautiously) that the plant I have seen in situ is A. acetosella, which is described in several sources as the "type species" of the genus.

If this is in Greater Seattle and the patch is growing wild in any fashion (they didn't plant it, it came up on its own etc.) - and especially if there is a possibility he can access the colony to make his own determination as to the identification - it would be a good thing to tell Arthur Lee Jacobson about it (contact information is on his web site).

If you haven't yet you might be interested in reading the 8 species accounting of Oxalis that are in the Checklist portion of his 2008 field guide Wild Plants of Greater Seattle - Second Edition.

Tough to find. Here is a UK nursery source:

http://shiptonbulbs.co.uk/WoodSorrelOxalisacetosella

I don't know if they ship here or not.

Here is a nice subspecies:

http://www.mountvenusnursery.com/catalog/product-html/Oxalis-acetosella-var-rosea-P-719.html

http://www.dhgate.com/product/oxalis-acetosella-rubra-windowbox-sorrel/138338356.html

another source of a subspecies, but not sure about this source...never ordered from them before.

Thank you, Lily777! I posted an enquiry to Wales as soon as I saw your link. I will keep you posted on the outcome.

Hey! Did you ever get ahold of this plant? I am looking for one for my supervisor. I would like to gift it to him before I graduate.