Several Suggestions for the Comprehensive Utilization of Spent Mushroom Substrate

In edible mushroom production, large amounts of spent substrate are generated every year, especially in long-established production areas and large-scale production areas. If these wastes are not handled properly and promptly, they will bring great hidden dangers to the development of edible mushroom production. At best, they cause environmental pollution and affect the yield and quality of future mushroom crops; at worst, they lead to the widespread spread and damage of diseases and pests, causing severe yield reductions or even total crop failure. Many mushroom growers remove the spent substrate from the mushroom houses and grounds after the growing season ends and pile it up around the mushroom yard for a long time to let it rot; others dump it into ponds, streams and lakes to soak for long periods. These handling methods do nothing but harm. Here are several suggestions and recommendations on how to handle and utilize spent mushroom substrate:

1. Reuse for cultivating shaggy ink cap mushrooms. For spent substrate from cultivating straw mushrooms, oyster mushrooms, shiitake, wood ear fungi, button mushrooms and other varieties, as long as the mycelium has grown well and the substrate has not been contaminated by competing fungi, it can be sun-dried, crushed and added at 30% to new raw material for cultivating shaggy ink cap mushrooms, and the benefits are considerable. This method can both reduce production costs and further improve the utilization rate of raw materials.

2. Process into spent mushroom substrate feed. There is still a large amount of mycelium in spent mushroom substrate, and the mycelium contains large amounts of protein and various amino acids that have not been utilized. Sun-dry in a timely manner and crush those substrates in which the mycelium grows white and clean and the substrate has not been contaminated, then add about 10% to feed to feed pigs, chickens and other livestock and poultry. This can likewise achieve the goal of reducing breeding costs and improving benefits.

3. Use as fertilizer for forestry and fruit growing, crops and flower planting. The various substrates left after mushroom cultivation are a high-quality organic fungal fertilizer. For example, in orchards of citrus, apple, pear, grape and other fruits, dig ring-shaped trenches 50 cm deep, apply the spent mushroom substrate deep into the trenches and then bury it. This can improve orchard soil, enhance fruit quality and increase yield and income. Moreover, the fertilizer effect is long-lasting and it is economically practical. It can also be used as a flower bud fertilizer for cotton and as a base fertilizer for sweet potato and potato, significantly increasing yield. In flower planting, mix the spent substrate left after mushroom cultivation with fertile soil, pile it up for natural fermentation, and use it as a base fertilizer for flower nurseries and potted plants. It improves the soil structure, aeration, and water retention and holding capacity for flowers. The flowers and plants grown are lush with branches and leaves and have brilliant blooms, and the cost is extremely low.

4. Use as sterilization fuel. For all bag-cultivated mushroom varieties, such as oyster mushroom, shiitake, wood ear fungus, enoki mushroom, poplar mushroom, tea-tree mushroom, silver ear fungus, reishi and lion's mane, sun-dry and store the spent mushroom logs after fruiting, then use them as sterilization fuel when producing spawn and cultivating with cooked substrate. This saves energy, saves production investment, and at the same time prevents environmental pollution.

5. Use as heating fuel for mushroom sheds. In winter and spring, temperatures are low, and it is very difficult for mushrooms to fruit in plastic sheds without raising the temperature. But most fuel used for heating is coal. Heating with coal not only requires large investment and has high costs, but is also a waste of resources. Mushroom growers only need to slightly modify the structure of the heating stove body, switching from burning coal to burning spent mushroom substrate, and they can save a large amount of fuel investment every year.