Gardening: Mushrooms pop up after recent rain

It’s amazing what cooler weather and some rain will do in a garden. Lawns have greened up, perennials have sent out another flush of flowers and tomatoes set on a bunch more fruits. The weather and the rain also brought out the annual crop of fall mushrooms in our lawns and garden beds.

Mushrooms are one of the oldest “plants” on Earth. I put “plant” in quotes because they aren’t really a plant as we would normally think. Rather they are the fruiting bodies of fungi found in the soil.

Fungi are an important part of the biological cycle that breaks down the old leaves, wood, needles and other organic detritus that fall to the ground. If you dig into a pile of old leaves or rotting wood, you will see lots of white threads running everywhere. The threads are the mycelium of the fungi. Using organic chemical processes akin to composting, the threads break down the organic material over time and return it to the soil as humus. Humus is the rich, brown material found in the soil.

The fungi reproduce by sending up the mushroom caps we see in lawns, gardens and the forest. Once the caps rise from the soil they open and disperse millions of spores from the gills underneath the cap. The spores drift on the wind and settle in a new place to start the cycle all over again.

One exception to this is the puffball mushroom. Puffballs are solid, white balls that can reach the size of soccer balls when they emerge in the fall. The spores are produced inside the ball that, when ripe, explode and send black spores out into the wind. Slugs, mice, skunks and other critters like to nibble on the mushrooms.

Are these mushrooms poisonous to people and pets? The rule for eating mushrooms is not to try them unless you know exactly what they are. Learning which ones are edible takes experience and a good teacher. Pets might be curious about them, so it is good idea to rake them out of the lawn or beds when you find them and add them to the compost pile.

One question that gardeners ask is why mushrooms appear in places they haven’t been seen before. Mushrooms often live on old buried organic material until the right conditions occur for them to fruit. That means, if you or a builder buried some wood debris from a building or tree-cutting project, the fungi will naturally grow into it. When conditions are right the mushrooms will emerge. They may stay for one season or many depending on the conditions.

The one exception to this is fairy ring mushrooms that appear as a circle in the lawn usually in the spring. Fairy ring creates dense mats of mycelium that expand and choke out grass. Controlling them is a long, hands-on process involving a pitchfork, dish soap and a month’s worth of time to get rid of them. If anyone needs specific information on that, email me.

———

Correspondent Pat Munts can be reached at pat@inlandnwgardening.com.