Steamed lobster dumplings with morel mushrooms. [Photo provided to China Daily]

"Usually, we should have wrapped up our business this time of the year, as exports to Japan, our main target, is ending. But this year, the demand has not started to wane yet," Yan says.

Considered a delicacy and given as a gift all year around in Japan, the Obon Festival, more commonly known as Japanese ghost festival, which falls on Aug 10 this year, is usually the peak period of demand for matsutake. The price of the fungus will experience a sharp slump after the festival as demand drops. But not this year.

The unusual weather has cut the reduced supply of matsutake by 90 percent, according to the association. This has prompted something of a fungi rush, with people flooding in to the province hoping to cash in.

"People who used to sell beauty products such as face masks and liquid collagen online are coming, and they have greatly disrupted the way we deal with local mushroom hunters by intercepting the mushroom hunters as they leave the forest and offering them unreasonably high prices for what they have picked," Yan says.

Yet, Yan admits, because of these people, he is making a higher profit even though he is selling less, as the price of matsutakes in Yunnan has rocketed to 3,000 yuan ($450) per kilo this year.

"I think if Shanghainese kept buying like this from me, and matsutake were available all year around, I would be able to buy my own apartment in Shanghai," jokes Yan, noting that at his online retail store on Taobao, more than half of the purchases were delivered to addresses in East China's Yangtze River region, especially Shanghai.