Mushrooms present a unique situation for those who care for lawns and gardens. On one hand, edible mushrooms can be a delicious addition for those who nurture edible gardens. On the other hand, many common garden mushrooms are poisonous and therefore mean danger for those with children and pets. They can also fall somewhere in the middle by spreading disease in turfgrass, trees, and other vegetation or by not being outwardly harmful, but simply growing in lawns and gardens where they aren’t wanted.
Fairy Ring Mushroom
Marasmius oreades, or fairy ring mushroom, is known for its distinctive growth pattern, referred to as fairy rings. Despite the name, however, fairy ring mushrooms are not the only mushrooms that grow in rings. Fairy ring mushrooms are light brown or off white in color, have a mild odor, and have caps ranging in size from just over half an inch to one and a half inches in diameter. These caps start out broad, like an umbrella, but as the mushroom matures, they begin to take on a bell shape. These mushrooms are edible, but there are several toxic look-alikes, so consumption of a found fairy ring mushroom is not recommended for people without mushroom expertise.
Meadow mushrooms, also called champignon, go by the scientific name agaricus campestris. Like fairy ring mushrooms, meadow mushrooms grow in rings. They have round, convex caps that can be anywhere from two to four inches in diameter. They are white or ashy grey, but bruise easily, and have a strong resemblance to the mushrooms you might find at the grocery store. Meadow mushrooms are most common in late summer and early fall.
The agaricus californicus is in the same family as the meadow mushroom, but while the meadow mushroom is edible, the California agaricus is mildly toxic to most people, so, again, it isn’t recommended that those without expertise attempt to identify and handle found mushrooms. It is of a similar size and color to the meadow mushroom, but may have a yellowish tint, especially where bruised, and may have a slight phenol odor. Unlike fairy ring mushrooms and meadow mushrooms, California agaricus grows in patches, clusters, or arcs, rather than rings.
Homeowners may be tempted to pull out an herbicide when they first notice unwanted mushrooms, just like they do when they notice weeds, but common garden mushrooms are fungi, not plants, so herbicides can do more harm than good. If you notice a mushroom in your yard, your best option is to break it apart or mow over it. If you have pets or children that may be tempted to sample the fungus, you should pick up the pieces and dispose of them. Your best option, however, is to engage in prevention to avoid unwanted mushrooms altogether.
There are three main causes of mushroom problems:
• Buried organic matter
• Excess moisture
• Low light
Fungi grow by breaking down organic matter in the soil. In your lawn, this could be buried timber, a tree stump, or leftover root systems. Generally, the easiest method of dealing with this is to simply do nothing. The mushrooms will stop growing once they’ve completely broken down the matter, but digging up the buried organic matter heavily disturbs your lawn. If you want to speed the process, you can apply nitrogen fertilizer at a rate of one half to three quarter pounds of fertilizer per 1,000 square feet of lawn. While we don’t get a lot of rain here in California, mushrooms can develop if homeowners overwater or if water isn’t allowed to properly escape or absorb into the soil. Aerate your lawn to ensure proper drainage and absorption, and try watering infrequently but deeply. Finally, if you have mushrooms growing in shady parts of your lawn, try trimming back tree limbs or bushes to let the sunshine in.
If after trying all these strategies you still struggle with mushroom problems, give the professionals a call. Lawnscape Systems is a leader in lawn care in Southern California. Whatever your problem, Lawnscape has a solution to solve it, and we only use the highest quality EPA certified products, so you never have to worry about the safety of what’s being used on your lawn. If you have stubborn problems with common garden mushrooms, weeds, or any other lawn care nuisance, get the help you need. Contact Lawnscape Systems today!