sweet white violet
It is with some trepidation that I venture into violet territory, as there are 117 species across the US, and violets are known to hybridize freely, so that identification often comes down to tiny little details.
According to the blog Mid-Atlantic Nature, nine white violets can be found in this area. A cross check with the Maryland Biodiversity Project shows that only six of these are present in the Maryland piedmont. And, the two shown in this post have some unique characteristics, so I’m fairly confident that they’ve been correctly identified.
As you can see in the pictures (if you zoom in), creamy white violet has two bearded petals, while sweet white violet has a reddish-brown stem .
Creamy violet is all over the place on Billy Goat C downstream of Carderock, with some occurrences upstream along Billy Goat B as well. I’m honestly not sure If I’ve seen sweet white violet in that area; You have to be pretty close to see the details. I saw this one plant (only this one plant) in Rachel Carson Conservation Park.
The two species have similar ranges, in most parts of the country east of the Great Plains, with V. blanda found further north and V. striata further west.
It’s possible that the sweet white violet pictured above is actually primrose-leaved violet, V. primulifolia, a naturally occuring hybrid of V. lanceolata and V. macloskeyi. I can’t really say without better pictures.