Which soil structure is commonly associated with compaction?

• A. Platy
• B. Granular
• C. Massive
• D. Prismatic

Answer: (A)

Compaction tends to squeeze soil into thin, horizontal plates, forming a platy structure. The pressure pushes particles into flat layers that stack, reducing pore space and making it harder for water and roots to move downward. This is the classic sign of compacted soil and explains why infiltration drops and rooting depth is limited. Granular structure, with crumby aggregates, signals good aggregation and aeration—not compacted soil. Prismatic structure shows vertical columns and relates more to horizon development than to compaction alone. Massive structure means the soil appears as a solid block with little visible structure, which can occur under heavy compression but is not the characteristic response; the plate-like arrangement is the telltale indicator of compaction.