Thatch

Thatch is the layer of living and dead stems, roots, and crowns that forms a type of blanket over the soil of your lawn. A small amount of thatch (one-half inch or less) is acceptable and even good for the lawn. But when thatch accumulates to over one-half inch, it can become one of a lawn's most serious enemies.

Keeps out the good and protects the bad

Like an old-time thatched roof, the thatch on your lawn creates a barrier which prevents the free movement of water, air, fertilizer, and insect controls into the soil. Since thatch is an ideal breeding ground for many diseases and turf-destroying insects, a heavy thatch layer can quickly become a serious problem.

Grass clippings not to blame

Contrary to popular belief, grass clippings are not the prime cause of thatch build-up. Clippings are almost all water. Once dried, clippings add very little bulk to the thatch layer. Thatch is mainly made up of the heavier crowns, stems and roots. Clippings of moderate length can be left on the lawn without fear of quickly increasing the thatch layer.

Reduces lawn care effectiveness

Heavy thatch prevents fertilizer and water from reaching the grass roots. This can result in a lawn that is thin, off-color, and prone to disease, insect, and drought problems.

You have two choices.

You can ignore the thatch, and hope it will decay before it does any harm. However, a thatch problem will almost always get worse with time, not better.

The second alternative, the option we most often recommend, is core aeration because it offers the least amount of disturbance to the healthy plants.

Crabgrass

Crabgrass is an annual weed. This means it dies completely every year and sprouts new from seed produced the year before. A healthy crabgrass plant produces up to 4,000 seeds during its short one-season life.

Why it's such a problem

Crabgrass is a very fast-growing plant. It has to be because it only has one season to live. Since it grows so fast, it can choke out slower-growing permanent grasses in your lawn. Once crabgrass gets a foothold, a cycle of summer crabgrass followed by winter weeds begins, leaving patches of bare dirt in the seasons in between.

Stopping the invasion

To get crabgrass under control, a thick stand of desirable grass has to be established. To do this in one season, the best approach is to concentrate on eliminating the crabgrass through the spring and summer. Use of pre-emergents (to stop the seed from sprouting) or post-emergents (to eliminate the plants once they germinate), or a combination of both is the best way to do this. Plan your seeding for late summer or early fall, and try to establish the new grass soon enough to mow it two to five times during the fall. Then an application of pre-emergent the following spring will be effective against any crabgrass, without harming your new turf.