Thistle in bloom close by the shore, the Isle of Skye, July 1988. The thistle is a national emblem of Scotland, going back to the 13th century, and is common throughout the land. "This proud and regal plant, which grows to a height of five feet, has no natural enemies because of the vicious spines that cover and protect it like a porcupine," to cite the home page of Historic-UK.