A purple color form of Pitcher's thistle

TitleA purple color form of Pitcher's thistle
Publication TypeJournal Article
Year of Publication2001
AuthorsVoss EG
JournalContributions from the University of Michigan Herbarium
Volume23
Pagination349-350
KeywordsVASCULAR PLANTS
Abstract

Cirsium pitcheri (Compositae), a thistle endemic to the sandy shores and dunes of Lakes Michigan, Huron, and Superior, has hitherto been known to have heads only pale (white or cream) in color. A new form discovered at the north end of Lake Michigan has rich magenta corollas of a shade like that of the usual form of C. vulgare. This phenomenon is the reverse of the more usual discovery of a pale (or albino) form of a normally colored species.