What do we mean by Dethatching?
Dethatching, as the name implies, means to remove portions of the thatch layer from the lawn. Excessive amount of thatch layer can stunt root growth from reaching deeper into the soil. This limits the roots' ability to access water reserves in drought and immovable nutrients.
What is Thatch?The thatch layer is mainly composed of lawn debris that are being broken down by microorganisms in the lawn. Thatch naturally occurs and protects the lawn from moisture fluctuations and soil compaction. On football fields and sports turf applications, thatch increases lawn resiliency, increases player footing, and lessens impact. However, having a thatch layer of more than 1" thick indicates that microorganisms in the lawn are having a hard time decomposing the lawn debris, which can harbor disease causing insects and pests. Fungi can breed in the thatch layer in the Winter, and attack the lawn in Spring to form Yellow Patch, Summer Patch, or Ring Spot.
Debunking the MythContrary to popular belief, mulching the lawn or otherwise leaving grass clippings or leaves on the lawn will NOT increase the thatch layer. Grass clippings and leaves are made up mostly of water and nutrients that can easily be absorbed by the lawn. According to University of Minnesota Extension, "grass clippings decompose rapidly and contribute very little to thatch accumulation." When it comes to leaving leaves on the lawn, Virginia Tech and Virginia State University says, "Mulching the leaves had no undesirable effects on turf quality or color, growth, thatch accumulation, soil pH, weed populations, or disease pressure. While the leaves did not prove to be a substitute for appropriate N fertilization practices, the general assessment was that mulching was overall very positive and economical."
Thatch Build-upExcessive thatch build up happens when the lawn produces more organic debris much faster than can be decomposed. According to Penn State University, "parts of grass plants that are the most resistant to decay — stem nodes, crowns, fibers of vascular tissues, and roots — make up the bulk of thatch." Mowing infrequently will contribute to thatch build up. This is because a significant amount of stem tissue gets cut off. As time passes by mowing one overgrown lawn after another, thatch layer naturally thickens as more and more stem nodes, crowns, fibers, and roots collect underneath the lawn. This is the reason why dethatching exists.
Thatch ManagementThatch Management calls for regular lawn maintenance. Get more frequent and regular weekly mowing, even when you think the grass has not grown yet. This limits the length of the grass to be cut and lowers the amount of organic matters resistant to decay. Mowing higher is also preferred to keep the grass lush and thick. Aerate and Top Dress regularly in Spring to reduce the need for synthetic fertilizer. Avoid the use of high yielding Nitrogen synthetic fertilizer. To get a greener look earlier into the growing season, add Iron instead of Nitrogen. Do not deep water lawns that are compacted. When the root system is restricted, there is no added benefit to watering deeply. Excessive moisture in the soil can become a paradise for fungal growth that may eat away the lawns' root system. But as the lawn thickens and recovers, gradually increase watering intervals and increase the amount of water at every watering time. Reducing the watering time may be needed for lawns with slopes and hills to lessen water runoff.
We hope that our little blog post helps you in understanding more about dethatching and thatch. Should you need help with your lawn, please do not hesitate to contact us. We are very eager to help.
50K Professional Lawn Services LLC. 844-505-5296. Austin, Texas.