Coltsfoot grows wild over much of Europe, and has been used traditionally to treat chest ailments for hundreds of years. The name is derived from the horseshoe shaped leaves. It was so popular in Europe at one time that French pharmacists painted its flowers on their doorposts. It was brought to the American colonies from Europe. American colonists were known to wrap persons afflicted with whooping cough in blankets that had been soaked with a coltsfoot infusion. Before the plant flowers, it resembles butterbur enough that old herbals caution against confusing the two.