Thatch

Thatch, that layer of dead grass roots and runners hovering just above or slightly below the soil surface, is caused by a number of things including poor watering habits, especially shallow watering; improper mowing techniques, especially cutting the grass too short or scalping the lawn; and the frequent use of high nitrogen fertilizers. It is not caused by a build-up of grass clippings.

If a lawn has a thick layer of thatch, a vigorous raking or the use of a mechanical dethatcher will get rid of it. Mild cases of thatch can be controlled by routine aeration. Prevent its return by mowing the lawn to proper height, probably a little higher than usual, by deep soaking the soil each time you water and by switching to slow-release fertilizers.

Also in this Episode

Gardening by the Yard : Episode GBY-103
•	The Great American Lawn
•	Mowing a Lawn
•	Mower Pollution
•	Lawn Fertilizers
•	Watering a Lawn Properly
•	Grass-Cycling
•	Aeration
•	Thatch
•	Weeds