Japan's beloved matsutake mushroom under threat

For diners with money to spare it is the taste of autumn but decline of red pine forests has left it with a precarious future

In a country that prides itself on its seasonal cuisine, few ingredients generate as much anticipation in Japan as the delicate, unmistakably autumnal flavours of the matsutake mushroom.

As the humidity of summer gives way to cooler days, it will soon appear on special display in supermarkets; upmarket ryotei restaurants will present delicate slivers in clear soups, or steamed with gently seasoned rice.