Coltsfoot or Colt's Foot (Tussilago farfara) is a strange looking plant, with its flowers resembling a dandelion stuck on an asparagus shoot. From February through to April this perennial sends up flowers that pre-empt leaf growth on upright leafless scaly stems. They are often found in patches with linking underground rhizomatous growth. I've found two patches this week near my home, one in an arable field amongst a crop for pheasant cover (see image), and the other on a roadside/woodland edge.
The plant has a number of alternative common names, including Coughwort. 'Wort' is often used as part of old names for plants with a medicinal use by combining it with the part of the human body they were believed to provide a cure or health benefit. So Coughwort was used as a cough remedy, Nipplewort (Lapsana communis) for sore nipples and Pilewort (Lesser Celandine) for guess what! Of course there was often very little evidence of medicinal benefits and was often simply based on the plant having the appearance of a body part, such as Spleenwort. However Coltsfoot does appear to contain some interesting chemicals, including 'tussilagone' with an anti-inflammatory action(*), which is of pharmacological interest. So maybe some of those medieval herbalists were on to something with Coltsfoot.
*Hwangbo, C., Lee, H.S., Park, J., et al. (2009) The anti-inflammatory effect of tussilagone, from Tussilago farfara, is mediated by the induction of heme oxygenase-1 in murine macrophages. International Immunopharmacology, 9 (13-14): 1578-1584