white mushrooms - Willamette Valley, near Albany, Oregon

Asked October 24, 2016, 7:15 PM EDT

For the first time in 15 years a huge amount of white mushrooms have appeared in my lawn. What

brought them on and how do I get rid of them? Located near Albany, Oregon - Willamette Valley

Oregon mushrooms

1 Response

We're definitely seeing a flush of mushrooms showing up this month due to the return of higher rainfall. Fungi (mushrooms are the above-ground fruiting bodies of the underground microorganisms) are nature's way of recycling organic matter - they are helping release nutrients back into the soil, so they are beneficial.

There are two general ways that mushrooms might show up in the lawn. The first are mushrooms that emerge from the soil above buried organic debris such as decaying tree branches and roots. These will generally be in a scattered area, or all in one particular spot. They will not harm your lawn, usually have one or two flushes each year and mowing will usually keep them in check. The other option is to dig up the soil and remove the decaying material that the mushroom is feeding on; but that might take quite a bit of digging.

The second pattern that you might see mushrooms growing in lawns is as a "Fairy Ring", which grows in an expanding ring across the lawn. Usually this initiates from a buried tree stump that is decaying. In this case, the fungi may kill the grass temporarily in a ring-like pattern (with a darker ring just on the outside where nutrients are being released). Making sure that the rest of the lawn is well-fertilized and well-watered will help make the darker ring less noticeable.

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