Kaempfer stayed two years in Japan, during which time he twice visited Edo and the "shōgun" Tokugawa Tsunayoshi. He conducted extensive studies on local plants, many of which were published in his "Flora Japonica" (part of "Amoenitatum Exoticarum"). When he visited Buddhist monks in Nagasaki in February 1691, he was the first western scholar to describe the tree "Ginkgo biloba". He brought some Ginkgo seeds back that were planted in the botanical garden in Utrecht. The trees have survived to the 21st century. (The "awkward" "–k"g"o" spelling appears to be an error Kaempfer made in his notes, a more precise romanization would have been "Ginkjo" or "Ginkio").