The Urban Pantheist

Photos by urbpan. Location: Ornamental cherry tree in front of Brookline Sewer and Water Division.

Urban species #286: Chondrostereum purpureum

Chondrostereum purpureum is a very common, widespread, and beautiful mushroom produced by a fungus that parasitizes a very wide range of tree species. When the mushroom is fresh it has a lovely silvery violet color. There is no generally accepted common name for it, though I tend to call it "violet tooth." This describes its color as well as the toothlike projections that make up the spore-bearing surface of the underside. The "teeth" are covered with cells that generate the reproductive spores of the fungus. It infects weak trees and feeds on the wood, causing a disease that affects the color and texture of the trees' leaves. Silver leaf disease, as it is called, mainly affects plants in the genus Prunus, such as apricot and cherry. Eventually the fungus spreads throughout the tree, and the mushrooms will be found growing on wood that is quite dead.