Yes, chipped branches of the Alnus tree can be used in growing Shiitake mushrooms. This was found in a study on “Using chipped Alnus as substrate for Shiitake (Lentinula edodes) in growing bags” conducted by Dr. Bernard S.Tad-awan, a professor from the College of Agriculture of the Benguet State University.
Alnus spp. is a common tree in the Cordillera Region. It is a nitrogen-fixing tree, which improves soil fertility. As used in Dr. Tad-awan’s study, Alnus trees were not felled. Small branches were trimmed from the stem and shredded into chips. The chips were then mixed with sawdust, rice bran, and lime and placed in black plastic bags as growing media for Shiitake mushrooms.
Dr. Tad-awan’s research showed that the ratio of 21:63:15:1(sawdust+ chipped alnus + rice bran + lime) developed the Shiitake in a short period of time. This substrate with the highest chipped alnus (63%) content gave the highest returns on cost and expenditures (ROCE), yield, and biological efficiency.
The many health benefits of the Shiitake mushroom fueled Dr. Tad-awan’s passion to study its production. The Shiitake mushroom contains lentinan, a polysaccharide, which is an immune-restorer. This content is responsible for the mushroom’s reported anti-carcinogenic, anti-tumor, anti-viral, and anti-bacterial effects.
Dr. Tad-awan pointed out that regular consumption of this mushroom can make the immune system strong enough to fight leading causes of death in the country like cancer and dengue.
Currently, Dr. Tad-awan is vigorously searching for ways to refine the best mix, considering that the chips can perforate the growing bags and thus increase the likelihood of contamination.
He also recommends the planting of Alnus trees as part of the re-greening program(s) in the Cordilleras. To further share the multi-benefits of the Shiitake mushroom, Dr. Tad-awan plans to conduct more trainings on shiitake mushroom production; establish market linkages for shiitake powdered-mushrooms; certify its organic production; and share R&D knowledge on mushroom nutriceuticals.
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