# Mouse-ear hawkweed (Pilosella officinarum) *Mouse-ear, pilosella; the medieval *Auricula muris*, mouse’s ear; *Pilosella officinarum*, formerly *Hieracium pilosella* of Linnaeus; in pharmacy *Pilosellae herba cum radice** **Known today as.** *Pilosella officinarum*, a small hawkweed of sunny banks, walls, and dry pastures, which Grieve says is told from every other British plant of its order by its creeping runners, “thrown out in the same manner as in the strawberry,” its rosettes of hairy undivided leaves, grey-green above and hoary beneath, and its single lemon-yellow flowers on stems a few inches high. The heads, about an inch across, have some fifty florets, the outer ones striped purple beneath, and they open, she says, at eight in the morning and close about two in the afternoon, from May to September. The whole flowering herb with its root is the medicine. Kind: Plant > **Caution.** Not for anyone sensitive to plants of the daisy family, Asteraceae, nor for anyone under eighteen, for want of data, nor where a reduced fluid intake is advised. Fever, painful urination, spasms, or blood in the urine call for a doctor. ## What was it used for? An astringent and wound herb. Its juice is less bitter and more astringent than that of its milky relatives, Grieve explains, and for that astringency it was much used in the Middle Ages as *Auricula muris*; she calls it a good remedy for whooping cough, “for which, indeed, it has been regarded as a specific,” and for all affections of the lungs, and the powdered leaves an astringent for bleeding. Culpeper gives the juice in wine for the jaundice “although of long continuance,” and the herb as “a special remedy against the stone,” for dropsy with succory and centaury, and as “a singular wound herb for wounds both inward and outward.” ## What does modern science say? The European Medicines Agency’s herbal committee accepts the herb with its root as a traditional herbal medicine, “exclusively based upon long-standing use,” for the relief of minor urinary complaints, taken with a sufficient intake of fluid to increase the amount of urine (monograph of 2024). Its assessment report lists hydroxycoumarins, chiefly umbelliferone, flavonoids including luteolin and apigenin glucosides, tannins, triterpenoids, and caffeic and chlorogenic acids. None of the old uses for the lungs, the jaundice, or wounds appears in the monograph. ## Pharmacognosy and toxicology - **umbelliferone**: chief of the hydroxycoumarins - **luteolin**: as glucosides, with apigenin - **apigenin**: - **chlorogenic acid**: with caffeic acid **Mechanism.** Not established in the sources read for this entry. **Standing.** European Union herbal monograph (2024): traditional use, “exclusively based upon long-standing use,” for minor urinary complaints. ## What lore surrounds it? Its English name is the medieval Latin one, and Drayton paired it with shepherd’s purse: “To him that hath a flux, of Shepherd’s Purse he gives, And Mouse-ear unto him whom some sharp rupture grieves.” The hawkweeds as a whole, Folkard writes, took their name from an ancient notion that hawks cleared their eyesight with them, which Gerard repeated, saying hawks were reported to clear their sight by putting the juice into their eyes; the Greeks held the plants holy as belonging to a sacred bird, and they were thought good for the eyes and against the bites of serpents and scorpions. ## What did the older authorities say? **Nicholas Culpeper.** “The Moon owns this herb also; and though authors cry out upon Alchymists, for attempting to fix quicksilver by this herb and Moonwort, a Roman would not have judged a thing by the success.” The apothecaries of Italy, he says, made a syrup of the juice with sugar, given for the cough and phthisic and “singularly good for ruptures or burstings,” and the green herb bound on a cut “doth quickly solder the lips thereof.” **John Parkinson, as Grieve quotes him.** Mouse-ear given to a horse “will cause that he shall not be hurt by the smith that shooeth him,” and skilful shepherds kept their flocks from pastures where it abounds “lest they grow sicke and leane and die quickly after.” ## Sources - Grieve, M. *A Modern Herbal*, “Hawkweed, Mouse-Ear.” As published on botanical.com. - Culpeper, N. *The Complete Herbal*, “Mouse-Ear.” Project Gutenberg, 49513. - Folkard, R. (1884). *Plant Lore, Legends, and Lyrics*, “Hawkweed.” Project Gutenberg, 44638. - European Medicines Agency, Committee on Herbal Medicinal Products. *European Union herbal monograph on Pilosellae herba cum radice (Mouse-ear hawkweed)*. EMA/HMPC/493453/2023, 20 November 2024. - European Medicines Agency, Committee on Herbal Medicinal Products. *Assessment report on Pilosellae herba cum radice*. EMA/HMPC/493454/2023, 20 November 2024. - European Medicines Agency, Committee on Herbal Medicinal Products. *European Union herbal monograph on Pilosellae herba cum radice (Mouse-ear hawkweed)*. EMA/HMPC/493453/2023, 20 November 2024. - European Medicines Agency, Committee on Herbal Medicinal Products. *Assessment report on Pilosellae herba cum radice*. EMA/HMPC/493454/2023, 20 November 2024. --- *Mouse-ear hawkweed.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-16. The Thinking Press. https://thethinkingpress.org/materia-medica/mouse-ear-hawkweed Historical description, not medical advice.