A farmer notices that plants in one part of a field are growing poorly, even though the topsoil looks healthy. What is the most likely explanation?

Healthy-looking topsoil suggests the A horizon is not the main problem. A compacted B horizon beneath it can block roots from penetrating deeper and prevent water from draining properly, which can limit plant growth. The most likely explanation is that the B horizon is compacted, limiting drainage and root penetration.

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