Poison ivy (Toxicodendron radicans)

In pop culture, poison ivy is often depicted as a troublesome weed due to its ability to cause severe skin irritation upon contact. Despite its innocent appearance, it can give a nasty rash to anyone who touches it. Interestingly, many animals consume it, and birds particularly enjoy its seeds. During the fall, its leaves turn a striking red. While Western poison ivy (Toxicodendron rydbergii) isn't seen as invasive in the U.S., it is considered a nuisance in Australia and New Zealand.