Thatch and How to Manage It:

Thatch is a dense layer of living and dead organic matter on the l surface.

Thatch in ls is often misunderstood; both its cause and control. Some ls have serious thatch proms while others do not. Thatch is a layer of living and dead organic matter that occurs between the green matter and the l surface. Excessive thatch (over 1/2 inch thick) cres a favora environm for pests and disease, an unfavora growing environm for grass roots, and can interfere with some l care practices.

The primary compon of thatch is turfgrass stems and roots. It accumuls as these plant parts buildup faster than they breakdown. Thatch proms are due to a combination of biological, cultural, and environmal factors. Cultural practices can have a big impact on thatch. For example, heavy nitrogen fertilizer applications or overwring frequly contribute to thatch, because they cause the l to grow excessively fast. Avoid overfertilizing and overwring. Despite popular belief, short clippings dropped on the l after mowing are not the cause of thatch buildup. Clippings are very high in wr cont and breakdown rapidly when returned to ls after mowing, assuming ls are mowed on a regular basis (not removing more than one-third of the leaf blade)

Environmal factors typically are another primary case of thatch. Conditions favoring thatch include heavy, wet ls; alkaline, or high pH ls; and l compaction. All are commonly met.

As thatch levels accumul to grer than 1/2 inch, l proms may begin, and the thatch needs to be controlled. Thatch may be torn out with a dethatcher or vertical mower, but will most likely return unless the cause is corrected. Mechanical dethatching is also very destructive to the l because roots are in thatch instead of l, so plants tear out easily. Overseeding is usually required afterwards. For this reason, it's best to tear out thatch in l August for optimum reseeding timing.

Core aerating helps degrade thatch and also helps solve some of the causes of thatch.

Core aerification, followed by topdressing are two methods that will generally correct the reasons thatch is accumulating. Core aerifying machines will pull up small l cores to the surface that are left there to act like topdressing. The holes cred help solve proms such as compaction or poor drainage. Topdressing is simply adding a thin layer(1/8 to 1/4 inch) of compati l over the thatch, which adds microorganisms to help in breakdown.

Aerifying equipm may be red or services are availa to do it for hire. Aerifying is an excell l practice with many benefits, as it helps solve l proms that in turn leads to better root systems and healthier ls. Aerify in spring or fall, making sure adequ moisture exists in the l. Make two trips over the l, the second perpendicular to the first. An average of 15 to 20 aeration holes per square foot is suggested. Cores should remain on the surface and allowed to air dry. These cores act as topdressing that helps degrade thatch. Additional topdressing mrial could be added after core aerifying if desired.