Thanks to a synergistic timing of rains, warm temperatures and summer fertilization, a great many of you may have seen a bumper crop of mushrooms in your lawns and flower beds. Which leads to myriad of questions I get on both the radio show and via email about how to control them. There really is no need! Thanks for your time, drive safely and have a great weekend!!!
Okay, I'll give you more information than that. But I will keep reminding you that is not all that necessary to perform control methods on mushrooms. With that said, let's start with the ones in the turf. They re commonly referred to as "fairy rings." Ask any plant pathologist and they'll tell you that they don't damage the turf. In most cases, pat yourself on the back and appreciate the high level of organic matter in your yard that is creating a type of saprophytic fungus where the main body of the fungus is feeding on the organic matter that is just under the soil.
They will continue to appear following wet weather – followed by warmer weather -- as long as there is more organic wood or thatch for the fungus to feed on. Once that has been consumed by the fungus, the mushrooms will disappear. However, that often takes several years to occur. The best solution is to ignore the mushrooms or rake them out or pluck them up when they appear. There is no "silver bullet" spray that will make them go away, not with out killing everything else in the soil as well. However, there are a couple of topical fungicide treatments that can reduce their numbers. Consan Triple Action 20 has been recommended for just such treatments for years on this radio show, and for those that want to lean towards a true organic method you can dust it with agricultural sulfur.
The next most often asked question is usually about whether such mushrooms are poisonous or not. While it is unwise to eat mushrooms from your yard, these kinds of mushrooms are not poisonous by definition. The organic matter that they grow in is what makes them poisonous. So, while that loosely translates into the fact that some are poisonous, the types of mushrooms that are found in yards vary by environment, the time of year, and the weather conditions, etc. so it is usually easier (and safer) to assume that any mushroom that appears in your yard is poisonous. So, it's never worth taking a chance and thus you should assume they are poisonous unless you know for certainty otherwise. Even those that grow in yards, that aren't poisonous by definition, are still somewhat toxic, thus stomach discomfort.
Other mushrooms pop up under living trees. Many of those are from another beneficial fungus known as mycorrhizal fungi. Basically, they're living in association with the roots of living trees, and sometimes they help the tree take up nutrients. Again, there is very little need for control measures since they are more a curiosity than a problem.
In areas where mushrooms appear in mulched landscape beds you may also see what is affectionately referred to as Slime Molds. These are primitive microorganisms that can produce white, yellow, orange or brown blobs or patches of fungus-like material known as sporangia (spores). Slime mold spore masses, when mature, are powdery and break apart easily during rain or when knocked around by your shoes. The spores of the slime mold survive in soil or organic debris and germinate during wet weather to form motile swarm spores. Some of these spores fuse to become amorphous amoeba-like structures that engulf other organisms or organic matter. Slime molds can actually move or flow across soil or plant surfaces. Although unsightly, these organisms are not pathogenic to living plant material. Here's a link to my tip sheet on Fungus in Mulch that we've referred people to for years.
In conclusion, remember that most mushrooms are a sign of good things in the soil. Thus, you don't need to attack them with an arsenal of sprays or dusts. Just remember to harvest them out before they open up and you will do your best to control their spread. I've given you a couple of light treatment methods, but I would also invite any idea you've employed that has shown success in eliminating these uninvited guests. Just let me know via an email response RandyLemmon@clearchannel.com Or give us a call on the radio show this weekend and share your method with the listening audience.
Be sure to check out Randy's Event Page to see where else Randy will be for the next few weekends. Bring your plants, bugs, and diseases for identification purpose.