When planting auricularia auricula, it is more appropriate to use birch core. Because birch core is the central part of birch, its fiber is shorter, its density is lower, it contains more lignocellulose and hemicellulose, and its lignin content is less, so it is easier to be used by auricularia auricula.
In contrast, birch bark has higher density, longer fiber, higher lignin content and more nutrients such as fat and protein, which is not conducive to the growth and development of auricularia auricula.