Japan's tropical wood imports were at a peak ( 25 million metric tons) , when these drums were made. The heavy dependence on Luan , began in the late 40's . It was the cheapest wood to convert into veneer because of it's easy availability from first the Philippines, later Indonesia , Malaysia and the fact that it's conversion rate during peeling was high. The trunks were big and straight. The use of Luan in all kinds of consumer goods , was an offshoot of the enormous Japanese postwar housing boom. There were almost 9 million metric tons of mostly Luan plywood, mfg. in Japan in 1973. By the 70's, supplies of Luan and tropical woods in general were running low and there were log export bans beginning to come into effect. Two other woods used around 1973, were Kapur( a harder ,more teak coloured tropical) and Sen, a native Japanese tree, one species of which is a source of camphor. Sen wood , smells a bit camphorous. About 70% of Japan is still forested and since the tropical hardwood restrictions of the early 70's , Japan has shifted to other sources of imports as well as the development of their domestic wood supply. Currently , Japan exports Sen plywood to North America! Walnut is out of the question, for a cheap ,Japanese export product----way too expensive. My guess would be Kapur.
Calfskin, you amaze me once again with you knowledge! Thanks for sharing!