Rediscovery of Malus baccata var. mandshurica at Nikko and the reexamination of its taxonomy

Abstract

"Nikko-ohzumi", which was discovered at the side of Lake Chuzenji in Nikko (Tochigi Pref.) and described as a new variety, Malus baccata var. nikkoensis, by Asami(l927) but ignored for a long time, was rediscovered. A detailed morphological reexamination indicated that it is impossible to separate this variety from var. mandshurica by tooth height and shape of the sepals, which were considered to be the distinguishing characters by Asami. The geographical distribution of M. baccata var. mandshurica (including var. nikkoensis) in Honshu was also reexamined. Malus baccata var. mandshurica grows disjunctively in the northern Tohoku district, the Chubu district (Nagano Pref. and Yamanashi Pref.) and Nikko. At Nikko, only about 60 plants were discovered and it is questionable whether this population is regenerating.