Lawn thatch is layer of living and dead organic matter which lies between the green shoots. It is a natural part of every healthy lawn and provides nutrients to the lawn as it decomposes. It can become a problem if this layer gets much thicker than about ½ inch and creates a barrier to natural air penetration to the soil beneath. In spring, many home owners either rent commercial thatching machines or hire a lawn service to thatch for them. But is thatching really necessary or the best solution? Decomposition of thatch requires a healthy population of soil bacteria which can be suppressed by low soil pH (acidic soil). This soil condition can also make it difficult to keep weeds under control. You may want to check you soil pH to make sure it is optimum for turf in your area (usually between 6.2 to 7.0). If your pH is low, an application of lime can help correct your soil to the proper pH, helping bacteria flourish, which will reduce thatch naturally and reduce weed pressure.