Ornamental and Turf Pesticide Applicators Practice Exam

What is thatch?

1. The layer of dead grass clippings

2. The layer of living and dead plant stems, leaves, and roots that develops between the soil surface and green vegetation

3. The topsoil layer of a lawn

4. The root system of a plant

The correct answer is: The layer of living and dead plant stems, leaves, and roots that develops between the soil surface and green vegetation

Thatch refers to the layer of living and dead plant stems, leaves, and roots that develops between the soil surface and green vegetation. It serves several important functions in the lawn ecosystem, including protecting soil moisture, contributing to nutrient cycling, and providing habitat for beneficial microorganisms. However, when thatch accumulates excessively, it can create problems by hindering water infiltration and air exchange in the soil, which may lead to root stress and increase susceptibility to pests and diseases. The other choices do not accurately describe thatch. The layer of dead grass clippings focuses on only one component of thatch, while the notion of topsoil pertains to the uppermost layer of soil that supports plant growth, distinct from the organic layer that makes up thatch. The root system of a plant refers specifically to the roots rather than the mixed organic matter of thatch. This comprehension is critical for anyone involved in landscaping or lawn care, as effective management of thatch can enhance turf health and performance.