Some Edible Fungi Growing on Trees in Northeast Woodlots - cover  

Some Edible Fungi Growing on Trees in Northeast Woodlots

Roger Monthey (USDA Forest Service, Durham, NH)
Rani Cross (Herbalist, Skyscraper Hill Organix Gardens, Brooks, ME)

 

Fungi that grow on wood abound in the forest ecosystems in the Northeast. Some of these fungi, when prepared properly, make tasty hot or cold beverages that serve as tonics. Tonics are defined in the dictionary as agents that restore or increase body tone, and which have invigorating, refreshing, or restorative influences. The use of these fungi for tonics has been known by herbalists for some time and has been the subject of workshops and seminars (e.g., Agroforestry Conference held in Portland, Maine from March 23-25, 2000).

This paper provides descriptions and photographs of the following species:

Chaga (Inonotus obliquus)
Birch polypore (Piptoporus betulinus)
Artist’s Conk (Ganoderma applanatum)
Hemlock varnish shelf (Ganoderma tsugae)
Tinder polypore (Fomes fomentarius)
Turkey tail (Trametes versicolor)
Reishi (Ganoderma lucidum)

Descriptions are adapted from Mushrooms of Northeastern North America by Alan E. Bessette, Arleen R. Bessette, and David W. Fischer (1997).

Uses of these mushrooms for other specific medical purposes is not the primary focus of this report, but we refer you to Christopher Hobbs’ 1995 book Medicinal Mushrooms: An Exploration of Tradition, Healing & Culture for more information. In addition, an article appearing in “Advances in Applied Microbiology” summarizes the current knowledge with respect to medicinal effects of one of these genera, Ganoderma. The authors concluded that while there may be an element of folklore in the use of mushrooms for medicine, modern research has shown some proven benefits such as regulating metabolism, fighting tumors, providing protection from radiation, preventing or reducing inflammation, synthesizing proteins, enhancing the synthesis of nucleic acids, lowering the concentration of glucose (blood sugar) in the blood, reducing blood pressure, having a tonic effect on the heart, and altering the body’s immune system (Jong and Birmingham 1992).

  Photo 1. Chaga growing on yellow birch.
  Photo 1. Chaga growing on yellow birch.

Chaga (Inonotus obliquus)
Description—Cap is 2 to 4 3/8 inches wide, resembling charred wood or canker-like growth. (Photo 1.) Outer part of cap is black, dark brown, or reddish brown; inner part of cap is bright yellow-brown to rusty brown. Cap is hard, brittle, and deeply cracked.

Habitat—Grows primarily on wounds and branch stubs on birches, but sometimes on ironwood, elm, alder, or beech.


 

Birch polypore (Piptoporus betulinus)
Description—Cap is 1 1/8 to 10 inches wide, shell to kidney-shaped. Cap surface is smooth when young (Photo 2), breaking into scales or patches with age (Photo 3). Cap is pale brown with darker brown streaks and an inrolled margin. Pore surface is white and smooth when young, becoming brownish with age. Pores are circular to angular in shape; tubes and pores become torn and tooth-like or jagged with age. Spore print is white. Stalk is lateral, white to brownish, and up to about 2 3/8 inches long.

Habitat—Grows on birches, solitary or in groups.

Photo 2. Birch polypore growing on decaying white birch trunk   Photo 3. Older speciman of birch polypore.
Photo 2. Birch polypore growing on decaying white birch trunk.   Photo 3. Older speciman of birch polypore.

 

 

  Photo 4. Artist’s Conk.
  Photo 4. Artist’s conk growing on decaying trunk showing brown dorsal surface and white ventral or pore surface.

Artist’s Conk (Ganoderma applanatum)
Description—Cap ranges from 2 to 26 inches wide, shelf-like to hoof-shaped, stalkless, and woody (Photo 4). Top of cap is hard, thick, and crusty, gray to grayish black or brown. Pore surface is white, staining brown. Brown spore color. Gets its name from the fact that the pore surface can be “drawn” upon; any etching on its surface turns dark brown. Artists often use the conks as a medium, finishing them with several coats of lacquer to preserve their work.

Habitat—Solitary or in clusters on hardwoods, especially maples.

 

 

 

 

  Photo 5. Specimen of the hemlock varnish shelf growing on downed eastern hemlock trunk.
  Photo 5. Specimen of the hemlock varnish shelf growing on downed eastern hemlock trunk.

Hemlock varnish shelf (Ganoderma tsugae)
Description—Cap is 2 3/8 to 12 inches wide, fan to kidney-shaped. Surface of cap is wrinkled and can range from shiny (appearing varnished) to dull and powdery. Cap surface is brownish red to mahogany near center or overall, brownish orange to reddish orange outward, and bright whitish on the margin (Photo 5). Pore surface is white to creamy white, becoming brownish with age (Photo 6) or when bruised. Pores are circular to angular in shape. Stalk is typically lateral, shiny, appearing varnished, and is brownish red to mahogany or blackish brown. Spore print is brown. According to Hobbs (1995), Ganoderma tsugae may have similar medicinal uses as Ganoderma lucidum, or the Reishi mushroom (see separate listing), used in Asia for centuries.

Habitat—Solitary or in groups on decaying conifer stumps, especially eastern hemlock.

Tinder Polypore (Fomes fomentarius)
Description—Hoof-shaped, stalkless, and woody (Photo 7). Flesh is thick, fibrous-tough to woody, and yellowish-brown. Pore surface is depressed and pale brown (Photo 8). Spore print is white.

Habitat—Solitary or in groups on decaying hardwoods.

Photo 7. Tinder polypore, shaped like the hoof of a horse, growing on white birch.
 
Photo 8. Dorsal and ventral view of tinder polypore (note pale brown ventral surface).
Photo 7. Tinder polypore, shaped like the hoof
of a horse, growing on white birch
  Photo 8. Dorsal and ventral view of tinder
polypore (note pale brown ventral surface).

 

 
  Photo 9. Turkey tail growing on decaying tree stump.

Turkey tail (Trametes versicolor)
Description—Cap is 3/8 to 2 inches wide, fan- to kidney-shaped. Cap surface is velvety to silky with conspicuous concentric zones (Photo 9). Zones are of various colors, usually with shades of brown, blue, gray, orange, and green. Spore print is white. Used primarily as tea, or dried and powdered and taken in capsules (Hobbs 1995).

Habitat—Solitary or in clusters, rows, or rosettes on decaying wood.

 

 

 
  Photo 10. Dorsal and ventral views of the Reishi mushroom.

Reishi mushroom (Ganoderma lucidum)
The Reishi mushroom occurs in New England according to a distribution map in the book North American Polypores (Gilbertson and Ryvarden 1986); however, it is considered rare in the Northeast according to several mycologists in the region that we contacted. Gilbertson and Ryvarden (1986) stated that Ganoderma lucidum is widely distributed in hardwood forest types in the United States, but is particularly common in the South, including the Gulf Coast region. Apparently, the mushroom’s prevalence increases from the north to the south throughout its range. The Reishi mushroom also grows in Asia, where it is widely cultivated for medicinal and cultural purposes, though wild specimens are preferred. Since the cultivated Reishi mushroom may be purchased in the United States in Asian grocery outlets, we included it in this report.

The Reishi mushroom is one of the so-called varnish conks, a group named for its shiny, varnished appearance. It closely resembles the hemlock varnish shelf mushroom but grows on decaying hardwoods, especially maples, rather than on conifers. It has a dark, reddish-brown cap with a creamy white margin (Photo 10). The Reishi mushroom is edible when prepared as a tea. The tea is traditionally prepared by powdering the mushroom. Powdering can be accomplished by cutting the mushroom into smaller pieces using a coping saw or other device, and then grinding it with a mortar and pestle. The powder is then simmered at a low temperature for 2 to 3 hours or until the original water level has been reduced by two-thirds. The tea can then be strained and sweetened with honey.

Early Chinese medical texts speak in reverence about Reishi’s purported power to heal and its “spiritual potency” (http//www.herb.com/herbal.htm). Reishi is also used extensively in the West, especially by those who practice yoga, Tai Chi, and meditation. The medicinal properties of the genera Ganoderma were discussed previously in this report.

Cooking Methods

Make sure your mushrooms are dry and hard. If still soft or pliable, let them dry in a warm, sunny location. The best way to cook these hard, woody mushrooms is to use the entire mushroom if they are small (up to 6-inch cap diameter or so), or fist-sized pieces if they are large (break mushrooms by use of a hammer or pliers). Place mushrooms (whole or pieces) in a pot with 2–4 quarts of water, depending on the quantity of mushrooms and the desired tea strength. Place the pot on a stove and bring the water to a simmer. Simmer for 20 minutes to one hour or so (use wood stove if you have one, and relax in your nearby rocking chair), until tea reaches desired strength. Allow tea to cool and strain it through a cloth. These teas act as a tonic, which helps to restore or increase body tone. These mushrooms can also be dried and ground into powder to be used in preparation of teas, or placed into capsules; however, this can be a dusty process.

Edibility Issues

The question “Is this mushroom ok to eat?” is often raised by both novice and experienced mushroom hunters, and rightly so. There is an old adage: “There are old mushroom hunters and bold mushroom hunters, but there are no old, bold mushroom hunters.” The bottom line is to be absolutely sure you know what you are picking. Conks, in general, are a relatively safe group of mushrooms. In addition, several of the fungi mentioned in this report often are found on specific tree species, which greatly aids in their identification. For example, the birch polypore and tinder polypore are often found on white birch, and the hemlock varnish shelf is found on eastern hemlock. With that said, however, we still strongly urge you to do the following before you attempt to pick any mushrooms for food or medicinal purposes.

  • Join a local mushroom club and go out with seasoned mushroom collectors to build up your own self confidence in recognizing edible fungi. This is the best way to become familiar with mushrooms.

  • Buy and study mushroom field guides. Field guides are an excellent source of information, but photographs and drawings are still not as useful as learning the mushrooms in the field with expert guides. Here are a few recommended mushroom guides.

  • Arora, David. 1986. Mushrooms demystified: a comprehensive guide to the fleshy fungi. 2nd ed. Berkeley, CA: Ten Speed Press. 957 p.

  • Bessette, Alan E.; Bessette, Arleen R.; Fischer, David W. 1997. Mushrooms of northeastern North America. Syracuse, NY: Syracuse University Press. 582 p.

  • Miller, Orson K., Jr. 1984. Mushrooms of North America. New York: Dutton. 368 p.

  • Lincoff, Gary H. 1997. National Audubon Society field guide to North American mushrooms. New York: Alfred A. Knopf, Inc. 926 p.

  • Smith, Alexander H.; Smith, Helen V.; Weber, Nancy S. 1981. How to know the non-gilled mushrooms. Dubuque, IA: Wm. C. Brown Co. 323 p.

After identifying a particular mushroom, you should still know that people have different physical and chemical tolerances. Mushrooms that are harmless to some people can produce unpleasant effects in others (Homola [n.d.]). Only take a small sample and test your body’s reaction before eating larger quantities.    


Published by:
USDA Forest Service
State and Private Forestry Northeastern Area
PO Box 640, Durham, NH 03824

Cover background photo: Bill Leak, USDA Forest Service; Durham, NH

Photo Credits:

Photo 1. Ken Dudzik, USDA Forest Service; Durham, NH.
Photo 2. Ken Dudzik.
Photo 3. William Frament, USDA Forest Service; Durham, NH.
Photo 4. Ken Dudzik, USDA Forest Service; Durham, NH.
Photo 5. Ken Dudzik.
Photo 6. Roger Monthey, USDA Forest Service; Durham, NH.
Photo 7. Ken Dudzik.
Photo 8. Ken Dudzik.
Photo 9. Dr. Kevin Smith, USDA Forest Service; Durham, NH.
Photo 10. Ken Dudzik.


Literature Cited:
Bessette, Alan E.; Bessette, Arleen R.; Fischer, David W. 1997. Mushrooms of northeastern North  America. Syracuse, NY: Syracuse University Press. 582 p.

Gilbertson, Robert L.; Ryvarden, Leif. 1986. North American polypores. Vol. 1. Oslo, Norway:  Fungiflora. 433 p.

Hobbs, Christopher. 1995. Medicinal mushrooms: an exploration of tradition, healing & culture.  Santa Cruz, CA: Botanica Press. 252 p.

Homola, Richard L. [n.d.]. Some common edible mushrooms found in Maine. Bull. 556. Orono,  ME: University of Maine, Cooperative Extension Service. 16 p.

Jong, S.C.; Birmingham, J.M. 1992. Medicinal benefits of the mushroom Ganoderma. Advances in  Applied Microbiology. 37: 101–134.