The “floral formula” is a shorthand method of setting forth the details of flower structure. The use of floral formulas helps us see features that tie together members of the same or related families. The various symbols (K for calyx, for example) vary among different instructions for writing formulas, but the overall approach is the same — communicating about flower structure. The instructions here are from an excellent (although outdated) book on plant taxonomy, “Vascular Plant Families,” by James Payne Smith, Jr. (1977) published by Mad River Press.
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