There are more than 700 plant species in the United States that can cause poisoning if a part of them is swallowed. In some cases, the entire plant is poisonous. In addition, cooking may alter the toxicity of some plants. Surveys have found that plants are second only to medicines as the cause of serious poisoning in children under 5. The problem is increasing, according to poison control centers, because of the growing popularity of houseplants, and also the number of families who make foraging for wild food a hobby.
Wild mushrooms are particularly notorious.
Although only about 100 of the 5,000 species of mushrooms found in the United States are poisonous, some of these, such as the amanitas, are particularly deadly. Cats and dogs frequently like to chew on plant leaves, and although most will avoid poisonous plants, kittens and puppies may not be so wise. In foraging for food during a hiking or camping trip, don't eat anything that you are unsure about. Don't let children nibble on anything that grows wild, including berries you know are safe. Many wild berries look alike and you can't expect a child to make such distinctions when you are not around.