Sheep Sorrel
We found these growing next to our rhubarb patch on June 15, 2024. This is an entire plant that I pulled up, from the root to the top of the flower spike is only about the length of my hand from wrist to fingertip (about 8 inches). Sandy said that when she brushed against them the flowers released a cloud of pollen, so they are one of the wind-pollinated plants that contribute to seasonal allergies.
While the flower spikes project fairly high, the leafy part of the plant is low enough that it would probably not be cut by a lawn mower.
While the leaves are kind of chewed up, we can see that they do have a distinctive shape – one long oval lobe, with two pointed lobes at the base sticking out to the side.
The blossoms are tiny, but kind of attractive under sufficient magnification. Still, it is pretty clear that they aren’t intended to draw insects, and instead spread pollen on the wind.
The best match for this I can find is Sheep Sorrel, Rumex_acetosella. It has the correct leaf shape, and the right type of flowers. Also, Sheep Sorrel is sour to the taste, and when I tasted a leaf off of this it was definitely sour, so I think we can take that as settled. This is an invasive European plant related to buckwheat.
Sheep Sorrel is considered a nuisance weed. It grows well in disturbed, acidic soils, and has a system of underground rhizomes that overwinter and help it spread, which makes it difficult to eliminate once established. On the plus side, it likes soil more acidic than most crop plants do, and so adding lime and extra fertilizer will usually help crops to outcompete it.
Some people like to eat this, since it is sour enough to be used the same way as one uses other sour plants, like rhubarb. I personally wouldn’t, though. At least some of the sour taste comes from oxalic acid, and oxalic acid in the diet can increase the chances of developing kidney stones. This is Not Desirable. I have not had a kidney stone myself, but I’ve known people who have. They do not recommend it. At all.