There is a widespread opinion that Sakhalin corktree and Amur
corktree are actually the same tree and thus the two names are synonymous.
However, those who live in the area where both trees occur find them
different. It seems that both have naturalized in the Boston area. Sakhalin
corktree produces fruit in October, while Amur corktree starts fruiting in
June. Photo credit Luba Batuner