The extremely poisonous hemlock plant has long been known for its deadly effects, and it is now making its way across the U.S. to parks, pastures and backyard gardens. Here is a visual guide on how to identify this invasive plant, where it grows, and how it can harm your body. The poison hemlock (or Conium maculatum) was initially brought to the U.S. from Europe as a garden plant, due to its attractive flowers. Hemlock commonly grows in the early spring, but in some locations can grow year-round as a perennial. #poisonhemlock #poisonplants #nature #environment