The Carlisle Mosquito Online

Friday, September 17, 2010


Dye Polypore

The Dye Polypore is the mushroom of a parasitic fungus. Fungi, which are not able to manufacture their own food, acquire it by one of three means. Some are saprophytic, feeding on dead organic matter like leaf litter, fallen trees, twigs and branches, or the dead tissue within living trees. We depend on these fungi to help clean up the woods. I consider them honorary members of the Trails Committee. Some are mycorrhizal, working in a symbiotic relationship with plants, trees and shrubs. I consider them honorary members of the Conservation Foundation. The remainder are parasitic, feeding on living plants and animals. They could get jobs on Wall Street. The Dye Polypore is a parasite of conifers.

The Dye Polypore's afoot (photo by Kay Fairweather)

Name: Dye Polypore is a good descriptive name for this mushroom. First it is a source of dye for animal fibers like wool or silk (I haven’t tried it on plant fibers like cotton). On the underside, where the familiar store-bought mushroom has gills, this mushroom has thousands of tiny holes or pores – therefore many pores or “polypore.” The binomial is Phaeolus schweinitzii where the genus name comes from the Greek “phae” meaning dark or dusky and the suffix “–olus” meaning less than or somewhat. So we have a name that means somewhat dark or dusky. The species name “schweinitzii” has the suffix “-ii” indicating that it is named after someone called Schweinitz. The man memorialized here is Lewis David von Schweinitz who was born in Pennsylvania in 1780 and is recognized by many mycologists as a founder of American mycology. His work produced systematic descriptions of mosses, ferns, lichens, flowering plants and over 3,000 species of fungi of which more than half were previously unknown to science. Of all those fungi, I do not know why this is the one chosen to bear his name. His biography indicates that he was a hard and diligent worker who contributed much to the body of knowledge of the natural world. Nothing of a parasitic nature shows up. Maybe he had enemies.

A young specimen. (photo by Kay Fairweather).

When and where found: Right now, my neighbor, Jon Golden, has a Dye Polypore near the base of a white pine. It appeared about 2 weeks ago and is still small – about 4 inches across. It is a fairly common mushroom in late summer and fall. They look like they are growing in the ground but are always close to a conifer of some kind and are connected to the roots of the tree. If left alone, they can grow to be more than a foot across. In other years I have found them in my own yard, in the Towle Woods and in Great Brook Farm State Park.

Distinguishing characteristics: This is a more or less flat-topped mushroom, up to a foot across, with a short thick stalk. When very young, it is a yellow hairy blob. As it matures, it flattens out and the yellow gradually darkens to browns and eventually black in its old age. The brown colors in a fully mature specimen often form a pattern of concentric circles. The upper surface is hairy, giving rise to another common name – the velvet-top polypore. The pore surface on the underside is greenish-yellow becoming brown.

Die (vs dye): The books do not list this mushroom as “poisonous;” they either show no entry at all under the heading of “edibility” or simply say “not edible.” It is not something that anyone (most people) would feel inclined to eat because it is tough and hairy. From the conifer’s point of view however, it is a pathogenic fungus that can cause the tree to die. It is the bane of Douglas Fir in western forests. It is one of the “brown rot” fungi so-called because they digest cellulose and leave behind the darker colored lignin. Since it works from the base of the tree, the disease is known as “butt-rot” (which sounds more like something that would afflict a couch potato). Wind-thrown trees are sometimes victims of butt-rot.

Dye (vs die): Many mushrooms can be used as a dye source but this is one of the ones that is a “strong” dyer. A rule of thumb for dyeing wool from mushrooms is to use approximately equal weights of wool and dried mushroom. With the Dye Polypore, you get a rich color using twice the weight of wool to weight of mushroom. The colors you can get include yellow, gold, orange, red-brown, olive-green, and dark brown. The main variables are age of mushroom, fresh vs dried, and mordant.

What, you’ve never seen a toadstool before? (Photo by Kay Fairweather)

References: Audubon Field Guide to Mushrooms, Gary H. Lincoff; Mushrooms of North America, Roger Phillips; Mushrooms for Color, Miriam C. Rice.

Submissions and ideas for the Biodiversity Corner are encouraged on any species that occurs in the wild and was seen in Carlisle. Send a note, a photo, or the whole column to If you have a mystery species, send that too. ∆

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