Pignut, Cow Parsley and Hogweed

 Smaller than its cousin the cow parsley, Pignut is only as tall as the grass.  I've cropped the photo so that you can just make out the finely divided filigree leaves near the bottom of the right hand picture.

Cow Parsley is much taller and the leaves are more ferny

Their big relation, the hogweed, is not in flower yet and the leaves are huge.