Georgia Pesticide Applicators Practice Exam

What is the main consequence of high levels of thatch?

1. Improved soil moisture retention

2. Better cosmetic appearance of lawns

3. Impeded water and fertilizer penetration

4. Enhanced microorganism activity

The correct answer is: Impeded water and fertilizer penetration

High levels of thatch in a lawn can create a barrier that obstructs the penetration of water and fertilizers into the soil. Thatch is a layer of organic matter, primarily composed of dead grass, roots, and other plant debris, that accumulates on the soil surface. When this layer becomes too thick, it can act as a sponge, absorbing water and nutrients that would otherwise reach the root zone of the grass. This impedes the essential processes of soaking up moisture and nutrients that are crucial for healthy plant growth. Inadequate water and nutrient penetration can lead to stress for grass and other plants, making them more susceptible to diseases and pests. Lower moisture and nutrient availability ultimately results in poorer growth and health of the lawn. The other options relate to benefits that may not accurately describe the effects of excessive thatch. While some thatch can improve soil moisture retention and provide aesthetic benefits, high levels create a problematic situation that can detract from lawn health rather than enhance it. Therefore, the primary concern in this scenario is the hindrance of water and fertilizer movement through the thatched layer.