Hericium erinaceus

In theory, this species of Hericium is easy to identify: it is the only species that forms a single clump of dangling spines, rather than hanging its spines from a branched structure.

Additional identifying features include the fact that it typically appears on the wounds of living or very recently cut hardwoods, and the fact that its spines are mostly more than 1 cm in length.

That's the theory. In practice positive identification is more difficult, since immature specimens of the branched species of Hericium often begin more or less as a single clump, and develop their branches with age.

Further confusion stems from the fact that the long-spined species of Hericium, like Hericium erinaceus, may have short spines (1 cm in length or less) when they are young. In short, you must be sure that your specimen is mature (look for signs of brownish or yellowish discoloration) before betting the house on your identification of Hericium erinaceus.

Ecology: Saprobic and parasitic; usually growing alone or in pairs; fruiting from the wounds of living hardwoods (especially oaks); late summer and fall, or over winter and spring in warmer climates; widely distributed in North America. The illustrated and described collections are from Illinois.

Fruiting Body: 8-16 cm across; consisting of one, unbranched clump of 1-5 cm long, soft spines hanging from a tough, hidden base that is attached to the tree; spines white, or in age discoloring brownish to yellowish.

Flesh: White; not changing when sliced.

Odor and Taste: Not distinctive.

Spore Print: White.

Microscopic Features: Spores 5-6 x 5.5-6 µ; globose to subglobose or subellipsoid; smooth or minutely roughened; hyaline and uniguttulate in KOH; amyloid. Gloeoplerous hyphae present, sometimes extending into hymenium to become cystidia (up to 50 x 6 µ, cylindric with knobbed apices, smooth, thin-walled).

Scientific classification

Kingdom:        Fungi

Division:          Basidiomycota

Subdivision:     Agaricomycotina

Class:   Agaricomycetes

Order: Russulales

Family:            Hericiaceae

Genus: Hericium

Species:           H. erinaceus

Binomial name           Hericium erinaceus

(Bull.) Persoon

Hericium erinaceus (also called lion's mane mushroom, bearded tooth mushroom, satyr's beard, bearded hedgehog mushroom, pom pom mushroom, or bearded tooth fungus) is an edible and medicinal mushroom belonging to the tooth fungus group.

Native to North America, Europe and Asia it can be identified by its long spines (greater than 1 cm length), its appearance on hardwoods and its tendency to grow a single clump of dangling spines. Hericium erinaceus can be mistaken for other species of Hericium, all popular edibles, which grow across the same range. In the wild, these mushrooms are common during late summer and fall on hardwoods, particularly American Beech.

Hericium erinaceus contains a number of polysaccharides, such as B-glucan, heteroglucans, heteroxylans, as several cyanthane derivative triterpenes known as hericenone and erinacine.

These latter compounds, found in the fruitbody and mycelium respectively, are considered to be responsible for the neuroregenerative effects of this species.

Hericium erinaceus is a choice edible when young, and the texture of the cooked mushroom is often compared to seafood. It often appears in Chinese vegetarian cuisine to replace pork or lamb. This mushroom is cultivated commercially on logs or sterilized sawdust and is available fresh or dried in Asian grocery stores.

Hericium erinaceus has long a history of use in traditional Chinese medicine. A 2005 rat study showed some compounds in the mushroom, like threitol, D-arabinitol, and palmitic acid, may have antioxidant effects, regulate blood lipid levels and reduce blood glucose levels.

A 2012 study on rats that had suffered brain injury showed that "daily oral administration of H. erinaceus could promote the regeneration of injured rat peroneal nerve in the early stage of recovery."

More recently and more relevant to human use, is a 2013 review of scientific studies, which asserted the medical benefits of the mushroom by saying "This mushroom is rich in some physiologically important components, especially β-glucan polysaccharides, which are responsible for anti-cancer, immuno-modulating, hypolipidemic, antioxidant and neuro-protective activities of this mushroom.

H. erinaceus has also been reported to have anti-microbial, anti-hypertensive, anti-diabetic, wound healing properties among other therapeutic potentials." A 2014 scientific review on the therapeutic effects of H. erinaceus concluded that "it is helpful to various diseases, such as Alzheimer’s disease, immunoregulatory, and many types of cancer."

A report reveals that pills of this mushroom are used in the treatment of gastric ulcers and esophageal carcinoma. A 2011 study on rats demonstrates the mushroom's wound healing capacities.

Considering the increase of degenerative conditions, scientists around the world have launched investigations on the possible anti-dementia compounds of this mushroom.