This beautiful garden/bedding plant, which has more than thirty thousand varieties, also has natural relatives. In Estonia, these include Iris sibirica and the yellow iris. Both have very beautiful large flowers. The flowers of the Iris sibirica are blue; those of the yellow iris, however, are yellow. As another difference, the leaves of the Iris sibirica are very thin (only about half a centimetre), while the leaves of a yellow iris are wide (1–2 cm). The yellow iris is not protected. They grow in many places, but usually, they are not seen in masses. They mostly grow in bogs, damp meadows, and forests. The rhizome of irises is large and strong – black dye can be made from it. However, this black substance is poisonous and corrosive. Therefore, fresh rhizomes and roots of irises cause severe inflammation in the mouth and throat. The poisonous substance decomposes upon drying. The seeds of the yellow iris have a bitter taste, which is why they have been added to coffee in desperate times.