The difference is that the hazel mushroom in Northeast China is wild and the Pleurotus ostreatus is cultivated.

Armillaria mellea, also known as Armillaria mellea, Armillaria mellea and Quercus variabilis, is one of the few wild fungi known by people but still unable to be cultivated artificially. It is a veritable "mountain treasure" and is called "the fourth treasure in Northeast China".