Identification

• Lawns with excessive thatch problems generally have bare patches or brown areas where the grass roots are unable to properly reach the soil. You may be able to see how thick the thatch layer is by examining the corner of the lawn where it meets the sidewalk. If it looks like it is over 1/2 inch, then you have a thatch problem contributing to an unhealthy lawn.
  
  

Problems with Thatch

• Thatch provides both pests and fungal infections with a hospitable home. Because air circulation is compromised, fungal infections like root rot can easily spread across the lawn. A layer of thatch over 1/2 inch can also prevent fertilizer from reaching the soil. Grass blades growing on a thick layer of thatch can eventually stop establishing roots in the soil and get tangled in the thatch.
  
  

Causes

• Improper cultural practices contribute to a thick thatch build up. Fertilizing a lawn with low amounts of nitrogen causes the root system to easily decay. Over-watering lawns depletes the oxygen in the soil, which hinders microbial activity that leads to the decomposition of thatch. Acidic soil inhibits also inhibits this activity.
  
  Both bent grass and Kentucky bluegrass vigorously grow creeping stems that lead to an excessive amount of thatch. Gardeners who plan to grow those varieties should be aware that they may have to remove the layer of thatch from their yard at least every other year.
  
  

Testing the Thatch Layer

• Find out how thick the layer of thatch is in your yard by driving a measuring stick through the grass and thatch to the soil. If your measuring stick cannot go through the thick layer of thatch, press a metal pole into the thatch and measure it with a measuring stick.
  
  

Solution

• Choose a time in the spring to remove thatch. Avoid fertilizing or planting grass seeds until the thick layer is removed, because it will not result in a successful yard.To remove thatch, rent a power rake from a gardening supply store. If you have a thick layer of thatch that is over 1 1/2 inches, you will have to remove the thatch twice. Removing too much thatch at once may damage the grass' root system.