Under normal circumstances, there are more than 1,000 cords of cordyceps per pound－the fewer the number of cords, the better the quality and the higher the price.

Cordyceps is produced by the combination of insects and fungi. The winter worm is 3 to 5 cm long with eight pairs of gastropods. The summer grass is shaped like a baseball bat, 4 to 11 cm long, dark brown on the surface, white when broken. Cordyceps fungus invades the larvae of the cordyceps bat moth in winter, absorbs nutrients, and develops mycelium. In summer, the fungus grows from the top of the dead insect's head, popping out of the soil surface, hence it is also called "summer grass". Cordyceps contains about 7 percent of oxalic acid (mannitol), about 25 percent protein, and 8.4 percent fat.