Thatch is the layer of living and dead stems, roots, stolons, and
rhizomes between the green blades of grass and the soil surface.
A thin layer of thatch (less than 1/2 inch thick) can be beneficial
to the lawn because it helps to limit weed germination, reduce water
evaporation, and protect from frost damage. However, thick thatch
layers can prevent water, air, and nutrients from penetrating the
soil, causing reduced root growth and increased potential for drought
stress. Thatch also favors fungal growth and can harbor insect pests.
Some turfgrass species, such as tall fescue and perennial ryegrass,
do not produce much thatch. Other turfgrass species, such as bermudagrass,
bentgrass, and Kentucky bluegrass, have creeping growth habits and
rapidly build thick thatch layers.
for preventing thatch build up
to reduce thatch