In the dark, damp woods, the first green signs of spring are showing on the ground. These are the leaves of dog’s mercury, which take advantage of the light before the tree canopy starts to shut it out. They grow quickly, and in many woods will soon form a carpet on the woodland floor. The leaves on the male plants are less jagged than those on the female plants. The flowers, some of which are already out, are greenish-yellow and very small.
Dog’s mercury procreates more by spreading its roots underground than by scattering seeds. It also has the unusual ability to retract its rootstock if some of this gets above the earth and starts to dry out.
It apparently acquired the “mercury” part of its name from the legend that the god Mercury revealed its medicinal powers to humans. However, these powers are rather dubious, because it is actually a poisonous plant — and seems to have got the “dog’s” prefix precisely because it is poisonous.