What is Fairy Ring and How to Get Rid of It

circular formation of mushrooms in grass called a fairy ring

When a perfect circle of toadstools grows in the yard, it often looks like a supernatural phenomenon. European folklore tells us these rings are where fairies dance and play and that a human should never step inside and disturb the fun. Whether or not fairies are involved, these rings in your yard are a natural occurrence caused by the fungal disease fairy ring. 

So what exactly is making your lawn so inviting to this fungal disease? And how can you get rid of it? Here’s what we’ll cover in the fairy ring guide below: 

How to identify fairy ring

Fairy ring symptoms are not always the same. For example, the fairy ring in your yard might appear as a dark green circle or as a ring of mushrooms. Depending on the symptoms, fairy ring is classified in one of three categories: 

  • Type I: This type of fairy ring appears as a ring of wilted, brown, dead grass and is the most damaging to your turf. The soil and thatch are extremely dry and nearly waterproof. 
  • Type II: The ring is dark green and grows faster than the surrounding turf. The dark green grass is due to the release of nitrogen and other nutrients as the fungus breaks down organic matter. 
  • Type III: The disease appears as a ring of mushrooms or puffballs. These symptoms typically occur after periods of frequent or heavy rainfall. 

Fairy ring symptoms may appear between spring and fall. The rings typically grow in a circle, but they also can occur as a half arc or semicircle. They can reach several feet in diameter. The largest fairy ring ever found is located in France. It’s about 2,000 feet in diameter and is estimated to be 700 years old.  

What causes fairy ring in the lawn?

The dancing fairies get a little help from different species of fungi in the fungal group basidiomycetes. These fungi feed on decaying plant tissue and live in the soil and thatch layer. 

So what can make your lawn particularly susceptible to the disease? Fairy ring fungi prefer to attack lawns that have: 

  • A thick thatch layer
  • Soils with low fertility
  • Low irrigation
  • Light-textured soils that are high in sand relative to clay.
  • Nitrogen-deficient turf

How to get rid of fairy ring in the lawn

Breaking up a dance party is difficult, but breaking up a dance party where humans aren’t welcome presents its own challenges. 

Fairy ring removal can be difficult and might even require the helping hands of a professional, depending on the disease’s severity. Or, if you’re suspicious about the folklore, you might not want to risk falling inside the ring. Hiring a trained professional can help ease those worries. 

So, how do we kindly ask the fairies to dance and play on a different lawn? Here are the measures you can take: 

  • For Type I symptoms (wilted or dead grass ring), aerate the soil and drench it with a wetting agent. A wetting agent is a chemical solution that allows water to penetrate and spread in the soil. The wetting agent is important because the soil and thatch of Type I fairy ring are a nearly impervious (hydrophobic) layer that prevents water from permeating into the soil.
  • Fertilize the grass with nitrogen for Type II symptoms (dark green ring) to mask the dark green overgrowth. This technique will not treat fairy ring, but it does remedy cosmetic problems. Use caution when applying the nitrogen, as applying too much can attract other diseases. Test the surrounding, uninfested soil so that you can better determine what a balanced nitrogen application looks like. 
  • For Type III symptoms, remove the fruiting bodies, as many of these fungi are poisonous. Removing the fungi won’t cure fairy ring disease, but it does improve the lawn’s appearance and protects curious children. 
  • Reduce thatch with a dethatcher.
  • Remove organic material, such as tree stumps and roots, to reduce the fungus’s food source. 
  • Aerate the ground to enable water to reach the root zone. 
  • Follow proper irrigation techniques. The best time of day to water the lawn is in the morning before 10 a.m. Watering infrequently and for long periods encourages a strong root system. 
  • Remove the turf, and dig out and discard the infested soil. Replace the affected areas with fresh soil and grass. Perform these steps 2 feet beyond the ring and to a depth of 3 feet. This method may prove successful in small infected areas

How to prevent fairy ring in the yard

Fairy ring removal typically offers short-term control of the disease because fairy ring can still re-establish itself. The best way to keep the disease out of the lawn is to perform preventative treatments.

Here are some lawn care practices that will help prevent fairy ring from developing in the yard:

  • Apply preventative fungicides. Fungicides are typically not useful as a curative treatment against established fairy ring, but they can be effective as a preventative solution. Always follow the product’s instructions when applying fungicide. 
  • Perform a soil test and create a balanced fertilization regime. A soil test will reveal what nutrients your soil is missing and how you can make amendments. 
  • Maintain proper watering techniques.
  • Remove old tree stumps, dead roots, and other woody materials from the lawn. 
  • Remove excessive thatch.

How does fairy ring spread in the yard?

Fairy ring survives as an individual fungus growing underground. The fungus produces small threads of mycelium in a circular or arch shape. The symptoms appear at the circle’s edge and gradually expand year after year as the fungus grows and gets older. 

The disease spreads to new areas via the movement of infected plant material or soil. The fairy ring mushrooms also produce spores that wind and water can spread to new areas. 

What grasses are susceptible to fairy ring?

It doesn’t matter what kind of grass you grow –– fairies will always find a place to frolic. All turfgrasses are susceptible to fairy ring disease. 

FAQ about lawn disease

1. What if I can’t identify the disease in my lawn?

Successful identification of a lawn disease is essential for your removal methods to be effective. The removal measures that work against one lawn disease might not prove so effective against another. If you misidentify the fungus growing in your lawn, you risk performing the wrong control methods and enabling the disease to progress. 

Identifying a turf disease with the naked eye isn’t always possible. And sometimes, only a trained professional can tell similar diseases apart. If recognizing the fungus in your lawn proves difficult, contact a diagnostic lab or turfgrass pathology lab for help. These labs specialize in diagnosing infected turf and are typically located at state universities.

2. What other turf diseases can infect my grass?

Fairy ring isn’t the only disease you need to protect your lawn from. Other turf diseases include: 

Anthracnose
Brown patch
Dollar spot
Gray snow mold 
Leaf spot and melting out
Pink snow mold 
Powdery mildew
Red thread
Rust
Summer patch

3. How can I prevent other grass diseases

The best way to prevent grass fungus is to perform a good lawn care routine. Most fungal diseases grow in lawns that receive little to no maintenance (or any maintenance they do receive is performed improperly). These lawns may have excessive thatch, weak root systems, or imbalanced nutrient levels. 

So how can you make your lawn less inviting to fungus? These 15 lawn care treatments are a great place to start: 

— 1. Remove leaves and other debris from the yard. Many fungal diseases will survive their dormant periods by overwintering in lawn debris, including leaves. A thick layer of leaves also can weaken the lawn by blocking the grass from sunlight.  

— 2. Mow your lawn regularly (and correctly). Maintaining your lawn’s recommended mowing height is essential for a healthy lawn. Cutting grass too short may stress your lawn and prevent it from photosynthesizing. Letting the grass grow too tall may invite pests and disease. Never cut off more than ⅓ of the grass blade during a single mow. 

— 3. Leave behind grass clippings. Grass clippings might look messy on the yard, but they are a healthy mulch for the lawn and will decompose quickly. Do not leave behind diseased grass clippings; otherwise, the fungus may spread. 

— 4. Perform proper irrigation practices. The best time of day to water the lawn is in the early morning before 10 a.m. Watering in the evening encourages long periods of leaf wetness that diseases thrive in. Watering infrequently and for long periods promotes a strong root system, while watering too often and for short periods encourages a weak root system. 

— 5. Invest in a sprinkler system. Sticking to an irrigation routine can prove challenging, especially if your lifestyle doesn’t involve early mornings. Consider installing a sprinkler system that caters to your lawn’s moisture needs and takes the load off your shoulders. 

— 6. Plant grass seed that’s disease-resistant and suitable for your lawn. Consult with a local lawn care professional about the best type of grass to grow in your yard. Not every grass type will grow well in your climate, and some grasses are more disease-resistant than others. 

— 7. Test your soil. Your lawn needs fertile soil if it’s going to develop a healthy root system. Test your soil to determine what nutrients it’s missing. 

— 8. Fertilize your grass. After testing your soil, implement a fertilizer regime that corrects the soil’s nutrient deficiencies.

— 9. Aerate compact soil. Compact soil is stressful for your turf because it prevents water, nutrients, and oxygen from accessing the roots. Core aeration creates small holes in the ground that relieve compaction and enable water, nutrients, and oxygen to penetrate the soil. 

— 10. Remove thatch that exceeds ½-inch thick. What’s that layer of dead organic matter between the soil and the grass? It’s called thatch. A thin layer of thatch is a healthy mulch for the lawn, but a thick thatch layer becomes real estate for fungi and pests. 

— 11. Overseed the lawn. Encourage new growth and a dense, green lawn with routine overseeding. 

— 12. Remove existing weeds. Your grass should be spending its energy toward growing healthy, not competing against weeds. When a weed invasion takes over the yard, your grass must expend its energy toward competing for space, moisture, nutrients, and sunlight. You can remove weeds with a post-emergent herbicide or hand-pull them. 

— 13. Apply pre-emergent herbicide. Pre-emergent herbicide doesn’t work against existing weeds. Instead, it prevents weeds from growing in the first place. This lawn care treatment is helpful for lawns that experience annual weed invasions. 

— 14. Control grubs and other pests. When grubs snack on your lawn’s root system, signs of weakness begin to appear, and the lawn becomes vulnerable to disease and other pests. Ensure your lawn’s health by removing and preventing pests. 

— 15. Spread compost across the lawn. Compost is a nutrient booster for your lawn’s soil. Apply compost by raking it across the yard as a top dressing or spread compost tea with a sprayer.

Lawn care pros: They make fungi boogie on out

Treating and preventing fungus takes sweat and long hours in the sun. But why let a lawn disease rain on your weekend parade? If you don’t want to spend your valuable free time worrying about a lawn fungus, hire a local lawn care professional to remove the disease for you. 

From dethatching the lawn to regular mowing, a lawn care pro can handle your yard work for you. By putting a good lawn care routine in place (whether it’s done by you or a professional), your lawn will be less susceptible to lawn disease. 

Main Photo Credit: Olivier Bruchez | Flickr | CC BY-SA 2.0

Jane Purnell

Jane Purnell is an artist, writer, and nature lover. She enjoys teaching readers about the importance of eco-friendly lawn care, integrated pest management, biodiversity, and sustainable landscaping.