Studies on udo, Aralia cordata THUNB. III

Abstract

Stocks of domestic and wild udos (Aralia cordata THUNB.), collected from various districts in Japan, have been cultivated in Sakai, Osaka Pref., and studies were made chiefly on their morphological characters with regard to the variations among the domestic and wild udos. Wild udos showed a wide range of variations as a whole, and their geographic variations seemed to be related to the latitude or altitude. They can be grouped into two types; the northern type and the southern type. The plants of the northern type, which are found in Hokkaido and Tohoku districts, have shorter hairs on their stems, less developed stipules, and less numbers of nodes, side shoots, and leaflets of the compound leaves, owing to their earlier blooming, than the plants of the southern type, which are growing in Kansai and western districts of Japan. In domestic udos, however, the range of varietal variation is not so wide, and all varieties observed are found to resemble to the wild udos of the sou-thern type. “Kan-udo”, which has short rest period and can be easily forced early in the season, was said to be introduced from Hokkaido. Our observations, however, revealed that it belonged to the southern type, basing on its morphological characters.