A Choice Edible Species - Honey Mushroom (Armillaria mellea)

The common name "Honey Mushroom" is a catch-all term ascribed to several members of the Armillaria genus, though in the Eastern United States, it is most often used to describe three distinct species: Armillaria mellea, Armillaria gallica, and Armillaria tabescens. All three of these species possess honey-brown caps that are slightly sticky when fresh, fibrous stems, and white, slightly decurrent gills. The spore prints of these species are all white, and, with the exception of Armillaria tabescens, they also possess an annulus (ring) on their stems. Below are a few images of Armillaria mellea I found fruiting on my most recent walk through the forest.

Honey Mushroom (Armillaria mellea):

These are choice edible species that begins fruiting in late Summer, though they are far more plentiful in the Fall months. The growth pattern of these species is cespitose, a term used by mycologists to refer to mushrooms that grow in dense clumps or clusters with their stems tapering and joining together at their base. While primarily acting as aggressive white-rot parasites on hardwood trees, honey mushrooms also act as saprotrophs digesting dead wood littered across forest floors. Even when not fruiting, evidence of honey mushrooms can be observed year-round by the presence of thick, black cord-like structures called rhizomorphs that allow the organism to spread across forest floors in search of new food sources. This strategy of expansion via rhizomorphs is so successful that individual honey mushroom mycelial networks have been known to extend for miles and live for thousands of years. The largest known Honey Mushroom network is located in the Malheur National Forest in Oregon, USA. Having covered over nearly 2,400 acres of forest in the region, the mycelial network has been affectionally named the "Humongus Fungus" by mycologists and US foresters alike.

Map and Table Depicting Location and Age of the "Humungus Fungus" in Malheur National Forest (Source: https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fsbdev3_033146.pdf)

While Honey Mushrooms are a highly sought after edible species by foragers, it is absolutely essential to know their poisonous look-alikes if one desires to forage for them. Please consult the advice of an expert mushroom identifier if you wish to hunt for and forage this species, and never consume any mushroom for which you are not absolutely sure of its identity. On my most recent walk through the woods, I came across one such poisonous look-alike species (Pholiota squarrosoides) fruiting from a log that also possessed a robust network of honey mushroom rhizomorphs. A less experienced forager may have identified the thick, black honey mushroom rhizomorphs and incorrectly assumed that the mushrooms with honey-brown caps and cespitose growth pattern emerging from the same log were honey mushrooms. While this would very likely not have been a fatal poisoning, eating this species is known to induce gastrointestinal distress as well as vomiting, particularly when combined with alcohol. This is an excellent example for why it is crucially important to not jump to any conclusions when identifying foraged mushrooms for the table; edible and non-edible species can grow side-by-side from the same substrate. Other look-alike species to be aware of in the eastern United States include Deadly Galerina (Galerina marginata) as well as the Jack-O-Lantern Mushroom (Omphalotus illudens). Deadly Galerina can be distinguished by its rusty brown spore print, and Jack-O-Lantern Mushrooms can be distinguished by their wavy-lobed orange to yellow-orange caps and yellow spore prints.

Sharp-scaly Pholiota (Pholiota squarrosoides):