The black fungus comes from Lesser Khingan's original forest. The original forest coverage of latitude 47 ° N is as high as 86.2% , and the green vegetation coverage is 97.4% . The high coverage of forest rain and green vegetation produces negative oxygen ions unique to the original forest, more than 30,000/cm3,25 times the size of a city, 18 times the size of a small urban area, 12 times the size of a plain area, and eight times the size of a typical agro-forestry area. The abundant negative oxygen ion + clean air + moist air humidity + latitude factor sooner or later the temperature difference is big, guarantees the fungus and so on mountain treasures fully absorbs the air nutrition in the growth process, it is not polluted and its nutrient content is much higher than that of other species of the same kind. The key is to ensure the color of black or dark brown agaric, thickness is good, taste has toughness, ear-shaped integrity. Black fungus has been green food certification and organic food certification