What do blue cheese, conks, penicillin, athlete’s foot, and soy sauce have in common? Fungus! These represent both the good and the bad that come from this amazing group of living things. Neither plant nor animal, the fungi inhabit a world mostly hidden from view, the mushroom-like things popping out of the ground often the only sign of their presence. Overall, they are immensely important for the well-being of our planet, playing the vital role of decomposer, breaking down dead plant and animal material. They are nature’s incredible recyclers.
This time of year, mushrooms, in a myriad of colors, shapes and sizes, can decorate a landscape. Interesting forms pop up out of wood chips that line walkways, dot vegetable beds topped with rich compost, and speckle lawns in places where birds or other wildlife may have left their calling cards. You might observe a clump of honey-colored mushrooms at the base of a tree, rusty colored spots on rose leaves, talcum-powder like coatings on shrubs or reddish-brown lesions on blades of grass. All are indicators of the presence of a fungus; the challenge is to differentiate those that are simply a nuisance vs those that might warrant action.
So, what’s a gardener to do when mushrooms appear? First and foremost, do nothing. No matter how interesting or appetizing a mushroom may look, the Mycological Society of San Francisco’s website, emphasizes to “always seek out expert assistance until you are experienced and absolutely sure of an identification. Proper identification of mushrooms is critical for your safety and health!”
Next, consider where the mushrooms are growing – if it’s on dead material (tree stumps, wood chips, compost), most likely the fungi are simply doing their job of decomposing organic material. If you observe symptoms on living plants, try to identify the culprit that’s causing them. The University California’s Integrated Pest Management (UC IPM) website is loaded with photos and information to aid you in identifying potential problems, whether on your roses, in your lawn, on your trees or in your vegetable bed.
Photo: Clathus ruber courtesy of UCANR