Which plant is commonly known to be poisonous?

Poison Ivy is widely recognized as a plant that can cause significant harm due to its poisonous properties. It contains an oil called urushiol, which can trigger allergic reactions upon contact with skin in many individuals. This oil is present in all parts of the plant, including leaves, stems, and roots. When someone comes into contact with Poison Ivy, they may experience rashes, itching, and severe discomfort, which are hallmarks of the allergic response.

In contrast, the other plants listed—Petunia, Daisy, and Marigold—are generally regarded as non-toxic and are often cultivated in gardens and landscapes without concern for poisoning effects on humans or pets. While some individuals may have sensitivities or allergies to these plants, they do not contain the same kind of toxic compounds that make Poison Ivy particularly dangerous. Understanding the characteristics of Poison Ivy helps individuals take precautions to avoid contact and recognize it in the wild.