The mushrooms that seem to magically appear almost overnight in our lawns are the fruiting bodies of a fungus. Fungi cannot manufacture their own food and must obtain it from an external source. In most cases, the clusters of mushrooms in our lawns are present because they are part of the natural process of decomposition of stumps or roots left from a tree removal or even from construction debris. Sometimes mushrooms appear to be marching across the lawn as they follow the path of a root underground. Do not worry about a few mushrooms in your landscape as they will not damage the lawn. If you find them unsightly, they can be picked or raked. They will generally disappear as the weather becomes dry.
There is another kind of mushroom that appears in lawn areas, and this one is worthy of some treatment. Fairy rings appear as circles of dark green or brown circles in the lawn. In wet weather, small tan mushrooms often appear in the ring. If you dig into the fairy ring you will find a white, fibrous net-like growth, the mycelium, throughout the soil. As the growth spreads, the ring grows along the outer edge. The mycelium can become so dense that water will not penetrate and the grass above it dies.
Fairy rings can be present on any kind of lawn but are found more often on dry, under-fertilized lawns. Control begins with good lawn maintenance. The spike and soak method is the only real method of control for fairy rings. Use a garden fork to make holes throughout the ring. The holes should be about four to six inches apart. The area must then be soaked every day or two for at least a month, especially if the ring has dry grass in the center. A teaspoon of dishwashing liquid in a gallon of water can be sprayed on the area before soaking. The soap will act as a wetting agent and helps the water soak into the affected area. If the ring is small, it is possible to remove the entire ring along with at least 18 inches of soil on each side of the ring. The soil must be removed to a depth of at least two inches below the mycelium. Fairy rings will die out when they approach sidewalks, flower beds, or other cultivated areas. Two rings meeting will also cause the death of both rings.
Mosses appear when grass is weakened by unfavorable growing conditions. Mosses prefer damp, heavily shaded areas and are often found on the north side of buildings. In addition, heavily compacted soil and low fertility encourage growth. Moss is not harmful to lawns but rather occupies the bare spots in lawns as grass thins. If moss is not deeply rooted, it can be raked out. There are chemical controls available but unless the conditions that encourage moss growth are changed, the moss will return. Several cultural practices will discourage moss growth. It is a good idea to plant shad-tolerant grasses or shade-loving plants or shrubs. Fertilize the lawn regularly. Avoid soil compaction by staying off wet lawns. If your lawn is compacted it can be aerated. Avoid overwatering. Reduce thatch by vigorous raking. Where shade is the result of trees and shrubs, pruning and thinning will allow more light into the area and better air circulation. As conditions that favour grass growth are improved, the grass will compete better with the moss.
It is important to remember that both mosses and mushrooms will grow when conditions are right for them to thrive. Sometimes, as gardeners, it is wise to bow to the forces greater than we are and to focus on other more important tasks.
Hanbidge is the Lead Horticulturist with Orchid Horticulture. Find us at www.orchidhort.com; by phone at 306-931-4769; by email at info@orchidhort.com; on facebook @orchidhort and on instagram at #orchidhort.
