Above, left: a view of the complete skirret plant; right: a closer look at the texture of the skirret root. Photographs by Corey Eilhardt.
Skirret (gerla) is hot and dry. Eaten in moderation, it is not very helpful or harmful. If someone should eat a lot of it, its heat and dryness would stir up fevers in him and harm his intestines. A person whose face has weak skin, which easily splits, should pound skirret in a mortar and add oil. When he goes to bed at night, he should rub it on his face, continuing until he is healed.
—Hildegard von Bingen’s Physica