Hemlock is a classical poison, being used as a form of execution regularly in ancient Greece, including on philosopher Socrates. There are several varieties, and in North America, water hemlock is the most common. You can die from eating it, and people still do, thinking it's an acceptable forged salad ingredient. Water Hemlock causes painful and violent convulstions, cramps, and tremors. Those who survive can have long term issues such as amnesia. Water Hemlock is considered the most deadly plant in North America. Serious note: Watch your children - even older ones - outside. If you forage, KNOW WHAT NOT TO EAT. Don't eat anything you aren't 100% sure is safe.