New thornless cultivar of castor aralia(Kalopanax septemlobus Koidz.) was developed and selected in Cheongsong, Prov. of GyeongSangbuk-do during the period from 1994 to 1999 by Korea Forest Research Institute(KFRI). The new thornless cultivar, "Cheongsong II" is characterized by a thinner outer-bark and soft, wider leaves, and is particularly characterized by thornless stems. This cultivar has a thinner outer-bark(8.82mm) when compared with thorned type trees(13.95mm). It also has a larger leaves than does thorned type trees. Consequently, the new thornless cultivar, "Cheongsong II" is defined to have thinner bark and longer and wider leaves than do other thorned type trees. thorned type trees.

• Sea-Hyun Kim
• Hyun-Kwon Jung
• Yong-Seok Jang