Oyster (Pleurotus ostreatus-pulmonarius, Pleurotus populinus) mushrooms are fruiting abundantly now!

Oyster (Pleurotus ostreatus-pulmonarius, Pleurotus populinus) mushrooms are fruiting abundantly now! They grace a wide range of hardwoods – including alders and birches (Betulaceae) as well as cottonwoods, poplars, aspens (Populaceae) – also maples and many other tree species, including conifers. They usually fruit both in the spring and fall, so when you find a spring fruiting, go back to that tree for another harvest in the fall. Delicate in flavor, but perishable, it is best to eat them within a day or two of collecting.

Oyster mushrooms are some of the easiest to grow, and they adapt to a wide range of substrates, due to a prodigious production of enzymes for digesting cellulose. As such, they are premier species for bioremediation of chemical toxins (mycoremediation).

A curious talent of oyster mushrooms is their ability to stun and consume nematodes. This is one avenue by which they accumulate and manufacture proteins. (Oyster mushrooms can have up to 20% protein.) And when they digest a substrate like wheat straw, about 20% of the mass becomes water. These mushrooms are water-makers!

Of all the species that can be cultivated, oyster mushroom species stand out for fighting starvation, hydrating arid environments, breaking down toxins and is, in my judgment, a keystone species in the ecology of forests. But be forewarned: insects love them too! So do birds, squirrels, and the dreaded slug. Competition for this fungal food!

For more information on the nutritional properties of mushrooms, including oysters, see my article “Notes on Nutritional Properties of Culinary–Medicinal Mushrooms” in International Journal of Medicinal Mushrooms, Vol. 7, pp. 103–110, 2005. 

Oyster mushrooms also contain cholesterol limiting compounds:  “Investigation of Lovastatin, the Anti-hypercholesterolemia Drug Molecule from Three Oyster Mushroom Species. (Mani Ramakrishnan et al. 2017. International Journal of Biomedical and Clinical Sciences Vol. 2, No. 4, pp. 26-31, 2017, http://www.aiscience.org/journal/ijbcs)

Oyster mushroom mycelium – upon exposure to blue light – produces shikimic acid, a precursor to the popular antiviral drug Tamiflu®:  (Kojima, M et al. Regulation of Primary Metabolic Pathways in Oyster Mushroom Mycelia Induced by Blue Light Stimulation: Accumulation of Shikimic Acid. Sci. Rep. 5, 8630; 2015. DOI:10.1038/srep08630.)

For more information on mycoremediation with oyster mushrooms, see Mycelium Running: How Mushrooms Can Help Save the World Ten Speed Press, Random House.