Lawn Thatch Control
What is Lawn Thatch?
All grass forms a layer of living and dead organic plant material, known as thatch. Thatch builds up between the grass blades and the soil. The primary component of thatch is turf stems and roots.
When thatch gets too thick, deeper than about one-half inch, it interferes with water and nutrients penetrating the soil and reaching the grass roots. Excessive thatch also creates a favorable environment for pests and disease. However, a proper level of thatch is desirable. It helps control soil erosion and reduces the evaporation of moisture from the soil.
How is Thatch Created?
Some varieties of grasses naturally tend to form a thick layer of thatch. Causes of thatch under our control include overuse of fertilizer, failure to water deeply, and not mowing frequently enough. Each of these can lead to a heavy layer of thatch.
It is a myth that leaving lawn clippings behind when mowing is a cause of thatch. The clippings in fact serve as a mulch by helping to reduce moisture evaporation and by returning nutrients to the soil as the clippings break down. Only if the lawn is mowed infrequently, or when wet can it cause problems for the lawn.
How Can Lawn Thatch be Reduced?
You can reduce thatch by raking the lawn or using a machine that slices through the thatch layer to break it up. Sprinkling a thin layer of topsoil or compost over the lawn will also help.
Ongoing control of thatch includes proper watering practices. Light watering moistens the topsoil, but it doesn't soak in. This forces the turf grass to extend its roots into the upper levels of soil to get the water. The excessive roots in the shallow topsoil are a significant factor in the formation of thatch.
Thatch is desirable when is in proper balance. The thatch layer helps to keep moisture in the soil by reducing evaporation. In a healthy lawn, microorganisms and earthworms help keep the thatch layer in balance by decomposing it and releasing the nutrients into the soil. So taking proper care of a lawn will help it to take care of itself.