🌰 In the UK you will find two main types of chestnut on the ground in autumn. 🗺️ Conkers are the seeds of the European Horse-chestnut, which is an ornamental tree introduced from the Balkans in the 16th Century. Sweet Chestnuts are the nuts of the Sweet Chestnut tree, which was introduced by the Romans for its edible nuts and versatile timber. 🤮 Conkers contain a poisonous chemical called aesculin, so cannot be eaten by humans or most animals, including horses, from which the tree gets its na