Hard, usually flat, zoned bracket fungus; reddish brown, shiny top. Grows at the base of living and dead deciduous trees or around stumps. May–November. Cap shelflike, semicircular; dark red to dark brown, lighter toward the margin; texture hard, shiny, often zoned. Pores circular to angular; whitish to brown. Stalk rarely present. Spore print brown. Spores magnified are elliptical, with double wall. When young and fresh, ling chih looks varnished, often with striking color bands of red, yellow, and white.
Lookalikes: Other Ganoderma species. The resinous polypore (Ischnoderma resinosum) exudes amber-colored droplets of moisture when young.
Cap width: 1–14 inches.
Habitat and Conservation
Grows singly or in groups of up to several, at the base of living and dead deciduous trees, and also around stumps.
Edible/medicinal. The ling chih is too tough to be a good edible, but in East Asia it is used medicinally to promote longevity and good health and is thought to prevent cancer. Recent studies in the West have shown that the ling chih stimulates the body’s immune system. It can be ground or purchased commercially and steeped for tea. The flavor of the tea is strong and bitter, but it can be balanced with honey or sugar.
This species lives as a network of cells (mycelium) within living trees as a parasite, and dead trees as a saprobe, digesting and decomposing wood. When ready to reproduce, the mycelium develops the bracket that emerges from the log—this is the reproductive structure. In polypores, spores are produced in the pores on the underside and are released to begin new mycelia elsewhere. The mycelium of a mushroom can live for decades.
Ling chih has been used as a traditional medicine in East Asia for thousands of years. While not common in the wild, it is now readily available cultivated. "Ling chih" means "mushroom of immortality" in Chinese. The Japanese name, "reishi," means "10,000 year mushroom."
Fungi are vitally important for a healthy ecosystem. This fungus feeds on hardwood trees, especially oaks, and on their fallen logs, branches, and buried roots. As a saprobe, it helps clean the forest and recycles nutrients back into the soil.
Mushrooms are a lot like plants, but they lack chlorophyll and have to take nutrients from other materials. Mushrooms are neither plants nor animals. They are in a different kingdom — the fungi. Fungi include the familiar mushroom-forming species, plus the yeasts, molds, smuts, and rusts.
Always be cautious when eating edible mushrooms. Be absolutely sure of the ID, and only eat a small amount the first time you try it to avoid a reaction..