The Darkening Wild
From the eastern edge of Mirkwood, the Long Marshes flank the Running River all the way to the shores of the Long Lake. Travel by river is the only way through – without a boat, you have many leagues of slogging through mud and fetid water ahead of you.
One native plant species, known as “gallows-weed”, grows in the Long Marshes and possibly nowhere else. When one makes contact with one of the hanging tendrils, it wraps around the neck and lifts the victim off the ground to strangle them. It is not known why this happens, but perhaps it is a carnivorous plant?