Shoppers at the Sunnyside Greenmarket in Queens last weekend scooped up fresh regional produce yet sidestepped the prized Ganoderma lucidum mushroom growing at their feet. This medicinal mushroom, more popularly known by Chinese and Japanese names, Lingzhi or Reishi respectively, is also indigenous to our region. You can find it at the base of common hardwoods filling our parks and lining our streets.
Identification of this fungus is easy — the upper fruiting body is often kidney shaped and is remarkable for looking glazed. Indeed, while Asian names reference divinity and immortality, the western scientific name derives from Greek and Latin roots for “shining bright skin. ” Apparently no one has studied the evolutionary advantage of the Ganoderma lucidum’s sheen.
This mushroom isn’t eaten because it’s bitter and tough, with a texture “like balsa wood or hard cardboard,” said Dr. Kathie T. Hodge, Associate Professor of Mycology and Director of the Cornell Plant Pathology Herbarium. This mushroom comes into the kitchen is as a powder that some people mix with coffee, or use to wholly replace coffee. Whether powdered or extracted by boiling or alcohol, it’s consumed for believed health benefits. Research into these potential benefits continues, but traditional uses include fighting tumors and viral infections, and generally boosting the immune system. The “red reishi” variety is considered more potent than the black.
Is your curiosity is piqued? Harvest. “It will die this fall, so if you want to hack it off, now is the time,” said Hodge. Under the section of the fruiting body that looks glazed is a duller white section riddled with tiny pores. These pores release spores, which are carried by the wind. Once that’s complete, this whole upper section rots off, often consumed by a green mold. “If you find it green, it’s too old. Don’t use it,” Hodge cautioned. This mushroom is also consumed by some rather specifically adapted beetles, both beautiful and bizarre. Their presence might quash some human appetites.
Foraging mushrooms can be dangerous, especially from urban tree pits. It’s best to go with an experienced forager to a natural area or to take a class, such as those taught by Gary Lincoff, author of The National Audubon Society Field Guide to North American Mushrooms and a New York Botanical Garden instructor. Or, Lincoff noted, it’s “sold in Chinatown.” Organic red reishi mushrooms are also sold at health food stores and online.
If you’re a determined forager finding only mushrooms that have gone green, don’t fret. They will grow back next year. Deep in the tree bark and roots is the mycelium — the complex base of the mushroom — ready to regrow a fruiting section next year. And check the maples, oaks, beech, sycamore, cherry, and birch trees in the vicinity. When spores land in a tree wound they take root and grow into new mycelia that then also fruit. The downside to Ganoderma lucidum is that its feeding on lignan, a plant compound, weakens trees. Hodge cited research pointing to a 30-year life span for red oaks with this mushroom, but noted that the stresses of an urban environment might hasten a tree’s demise. The death blow is very likely to be a windstorm toppling the enfeebled tree. One interesting note is that many of the antioxidant and anti-carcinogenic benefits of Ganoderma lucidum are also attributed to lignans themselves.