Another plant that children often handle during craft projects at school is cotton. Gossypol is a toxin that naturally occurs to help prevent insect damage to the plants. However, if you have a child who often chews objects or puts things in his mouth, do not leave potentially toxic seeds or cotton balls where the child can reach them. Trees Trees that can be poisonous include oaks and the black locust. The leaves and acorns from oak trees can be toxic if eaten in large amounts.
Symptoms normally appear after several days or weeks and the kidneys are usually affected.
Symptoms of this poisoning are nausea, weakness and depression. Go on a nature walk and watch a squirrel or chipmunk as it finds nuts and berries. Explain that every animal, including people, have certain foods they can eat. A squirrel can eat acorns, but people should not because it can make them sick. Some plants in the nightshade family can be toxic.