Today I Am…

Random pictures of small blue things (and purple things), because once again I haven’t the time to write meaningful content.

I don’t know if this is a color variation of common blue violet (Viola sororia) or something else. There is a well-known white form, sometimes called Confederate violet, but it doesn’t look quite like this one. Violets are notoriously promiscuous so who knows. The color is remarkably consistent every year. I’ve only seen them at Rachel Carson Conservation Park.

If you see a blue violet that stands well above the level of its leaves, and if it’s growing in or very near to open water, then it’s probably marsh blue violet (Viola cucullata).



Wild geranium (Geranium maculatum), also at RCCP. These two were somewhat bluer than is typical.




Virginia spiderwort (Tradescantia virginiana) There aren’t many three-petaled flowers around.




Only one of the seven species of Oxalis found in Maryland is an alien, but some of the others can be awfully weedy. I like them anyway. I’ve been on the hunt for Oxalis colorea, previously overlooked here until a fellow botanerd found it [hi, Bill]. If I make any progress I’ll write about it. In the meantime, though, you just can’t call violet woodsorrel (Oxalis violacea) a weed.

Even the leaves are charming.





Two Woodsorrels

Reviled by gardeners, yellow woodsorrel seems to show up everywhere. I’m not sure I’ve ever purchased a gallon-size or larger plant of any sort from a nursery that didn’t have the darned thing tagging along.

I’ve never bothered to key out a sample (maybe I will soon, when it isn’t raining; it won’t be hard to find), but the little plants that some people mistake for some sort of yellow clover are likely Oxalis stricta or O. corniculata, both of which are listed as weedy or invasive by several authorities. Oxalis species have leaves that resemble clover’s, with three heart-shaped leaflets, but clover is in the Fabaceae while Oxalis is in its own family, Oxalidaceae.

But this post isn’t about the weeds. It’s about two other woodsorrels, both with lovely flowers. Both form colonies from runners along the ground, but they aren’t weedy. If I found these in my garden, I wouldn’t pull them out.

The purple flower photobombing the first picture in yesterday’s post is Oxalis violacea, violet woodsorrel. It’s a perennial forb found from the Great Plains east to the Atlantic, as far north as Vermont and south into Florida. It’s listed as endangered in Massachusetts and Rhode Island, threatened in Michigan and New York, and special concern in Connecticut. The leaves are typical for this genus except for the purple markings, which may be very faint but at this time of year are usually quite distinct. Like many oxalis species, the leaflets fold together when there is little light (including overcast days). The flowers are about half an inch wide.

The flowers of the other species, Oxalis grandis (great wood sorrel), can get even larger, up to an inch across. Note the orange-red markings in the throat (click on the picture for a larger view). There are several species with this characteristic, but none of them are found in Maryland, making this an easy plant to identify when found here. This species is somewhat more upright than other Oxalis species.

Great yellow woodsorrel has a much smaller range than violet woodsorrel: it’s found from Pennsylvania south to Alabama and west to the Mississippi River.

See the larger, deeply lobed and serrated leaves in this picture? They belong to a different yellow flower. More on that, and a closely related alien, next time.

Two Wood-Sorrels


common or yellow wood sorrel
Oxalis stricta





violet wood sorrel
Oxalis violacea




The yellow-flowering species is derided by some [hi, Linda!] as a real nuisance plant. It is pretty, though. Is it a weed? Not when I find it in a natural setting like the Potomac gorge, where it doesn’t seem to grow in large swaths like it does in the garden. Yellow wood-sorrel is found all over the US except Oregon, California, Nevada, and Utah, and is listed as a weed by some authorities. It seems to have a long bloom period in the wild.

Violet wood-sorrel is found in all US states except Montana, Idaho, Washington, California, Nevada, and Utah. The plants hug the ground, but the flowers stand a few inches taller than the yellow species, and it doesn’t bloom as long. I’ve seen it in the gorge forming carpets as large as half a square meter. Before blooming, the leaves often have a violet tinge, especially on the edges, but it always seems to be gone by bloom time. A large patch never seems to produce more than a few flowers, but then this is only the third year I’ve observed it.


I feel it’s time to re-post this.