Compare core aeration and spike aeration, including their effects on soil compaction and thatch.

• A. Core aeration removes soil plugs, relieving compaction and reducing thatch; spike aeration creates holes without soil removal, less effective for compaction relief and thatch reduction
• B. Core aeration uses spikes; spike aeration removes soil plugs
• C. Core aeration worsens soil structure; spike aeration reduces compaction more
• D. Core aeration removes soil plugs and increases compaction; spike aeration removes thatch only

Answer: (A)

The main idea is how the two aeration methods change the soil structure and surface thatch by how they interact with the soil in the root zone. Core aeration removes small plugs of soil, which physically loosens the compacted layer and creates open channels for air, water, and roots to move more freely. Those soil cores also bring organic material toward the surface, where it can decompose and, in the process, help reduce thatch as microbial activity is stimulated and the surface becomes more manageable to rake or overseed.

Because soil plugs are removed, core aeration increases pore space and drainage, and the removal of some thatch-laden material along with the cores directly contributes to thatch reduction over time. Spike aeration, on the other hand, uses solid tines to poke holes without removing soil. This leaves the surrounding soil in place and can even lead to compaction around the openings when the holes collapse, so the overall relief of soil compaction is limited. Since no material is removed, thatch isn’t effectively disrupted or reduced, and the surface remains more prone to thatch buildup if not followed by dethatching later.

So, core aeration removes soil plugs to relieve compaction and helps reduce thatch, while spike aeration creates holes without soil removal, offering less relief for compaction and less impact on thatch.