the root of this plant was used in a medicine for treating a skin ailment around the mouth
The Florentine Codex, Book 11, folio 15v, has an illustration of this plant and a description, saying how it grows in the fields and in the mountains, the leaves are "useless," but the single, yellow root is ground for an infusion that is to be drunk when fasting and for people who are feverish and have diarrhea. (paraphrasing, SW)
la raíz de esta planta se usaba en un medicamento hecho para combatir la sarna de la boca