Keep any poisonous plants, bulbs and seeds out of reach of younger campers. Do not assume that a plant is safe simply because you've seen birds and other animals eat it. Rememer that cooking plants does not always kill poisons in the plant. Do not use any potentially poisonous twigs as cooking skewers or firewood. Well-known alkaloids include nicotine in tobacco and caffeine in coffee.
Alkaloids often have a bitter taste and are insoluable in water.
Cyanogenic glycosidee are the toxic components of cherry leaves, peach pits and apple seeds. Cardiac glycosides include the medicinal and toxic components of Foxglove, as well as those found in Oleander and dogbanes. They may increase heart function in medicinal dosages, but in toxic doses, they may cause cardiac arrest. Members of the arum family are well known for containing calcium oxalate in the form of small, insoluble crystals. If chewed, they cause intense burning and irritation of the mouth.