European Stinging Nettle
This invasive plant has been introduced to many areas of the Mid-Atlantic and the Southeast. It is covered with fine "hairs" that create a fire-like pain on contact. While these hairs may look soft, clear, and harmless, do not be fooled: they are the bane of hikers on the trail. This is evidenced by "AT-AT Walker's" 2016 online journal entry in which he mentioned that they grow in patches so thick, whole stretches can be covered by it. The plant was originally found in the Western United States, but it can now be found in the Appalachian Trail area. This plant is a threat not only because of its stingers, but the thick bunches it grows in can also use up space and sunlight that native, less harmful plants need.