comprises three cytotypes: a sexually reproducing diploid, an apogamous triploid, and an apogamous tetraploid. Isozyme studies by G. J. Gastony and L. D. Gottlieb (1985) suggested that the apogamous triploid is an autopolyploid derived from sexual diploid populations. The apogamous tetraploid apparently resulted from hybridization between diploid and triploid individuals. These cytotypes have not been formally recognized as subspecies because their ranges seem to overlap extensively and because the ploidy level of the type collection of P . andromedifolia is not known.