Hardwood Sulfer Shelf, Laetiporus gilbertonsii (by )

Mushroom of the Month: November, 2018

While we wait patiently for the fall rains to arrive, there are still some interesting sporocarps lurking in our local outdoor spaces. Oyster mushrooms (Pleurotus ostreatus) and the Prince (Agaricus augustus) often fruit in the summer fog season, and Dead Man’s Foot or the Dyers Puffball, (Pisolithus arhizus) pops up unexpectedly in dry meadows and sandy trails with hardly any moisture. But one of the most spectacular dry season fungi is the Hardwood Sulfur Shelf, Laetiporus gilbertsonii.

In our area, L gilbertsonii is found on eucalyptus, oak, and other hardwood species. It can grow on logs, stumps, or on dead or living trees and can fruit in inland valleys during the driest part late summer without any sign of nearby moisture. It first appears as a small blob, expanding into broad semicircular shelves that can form rosettes or impressive clusters with overlapping layers. The main body is a striking salmon pink to orange color with bright lemon yellow or sulfur yellow pores on the undersides of the tips. When fresh, the colors are vibrant and the texture is soft and spongy. With age, the fruiting body slowly turns lighter in color and becomes harder and more brittle, eventually turning dull white. Crumbly remnants can persist for months before slowly weathering away.

Laetiporus is a brown rot fungus, a type of saprobe which breaks down the cellulose in dead wood. The effected wood will often appear brown, cracked, and shrunken with a soft brittle texture. It is also parasitic, so living trees can be hollowed out and drop large branches or break in strong winds, so you have reason for concern when you find this fungus on that old oak tree that is shading your house.

But on a more positive note, when fresh and tender, Laetiporus gilbertsonii is a prized edible, commonly referred to as “chicken of the woods.” It is one of the “foolproof four” wild edible mushrooms recommended by Clyde Christianson in his book Common Edible Mushrooms, first published in 1943. Along with the giant puffball, (Calvatia gigantea), morels (Morchella sp.), and the shaggy mane (Coprinus comatus), “chicken of the woods” was considered to be a choice edible that was both abundant and distinctive enough that a prudent beginner could easily identify it without risk of confusion with any dangerous species. But of course nothing is completely foolproof. Christianson’s “chicken of the woods” was Laetiporus sulfureus, which has since been divided into at least eight distinct species including our L. gilbertsonii and another western species L. conifericola, which not surprisingly grows on conifers. Most of the species are so similar, that they cannot be differentiated by macroscopic or microscopic physical characteristics alone. Looking at the species of wood they are growing on, location on the tree, and

region where they are found provides some clues, and DNA sequencing is ongoing to clarify the definitions of this group of similar species. Luckily, all seem to be relatively safe edibles.

What is meant by relatively safe, you might ask? Just like chicken, chicken of the woods should be cooked thoroughly. Though it is not fatal, people have been sickened by eating raw or undercooked Laetiporus. Only tender young fruiting bodies or the tender outer tips of older specimens should be eaten. There are reports of gastric upsets caused by fungus harvested on eucalyptus, though many people (including the author) have eaten L. gilbertsonii from eucalyptus without any ill effects. Still it is best to eat just a bit the first time to make sure you don’t have a bad reaction. L. conifericola is equally edible and should be treated with the same precautions. And again, don’t forget to cook it thoroughly.

But when well cooked, this mushroom does make a good chicken or meat substitute. With its firm flakey texture and a bit of imagination, some people claim it tastes just like chicken (or snake or turtle etc). There are about as many ways to cook this mushroom as there are to cook chicken. Here is one recipe to start with, Curried Green Beans with Sulphur Shelf

 

`