Topdressing sand on high-sand rootzones has no effect on microbial activity.

Topdressing sand on high-sand rootzones has no effect on microbial activity.

• A. True
• B. False
• C. Sometimes
• D. Never

Answer: (B)

Topdressing with sand changes the physical environment of a high-sand rootzone in ways microbes respond to, especially moisture, aeration, and temperature. Sand layers alter pore size distribution and drainage, which can improve oxygen availability and reduce anaerobic pockets, shifting the microbial community and activity. At the same time, the surface layer can dry out more quickly, potentially reducing microbial activity when moisture is scarce, until moisture cycles restore conditions. Because these factors directly influence microbial metabolism and habitat, adding sand does not leave microbial activity unchanged. The statement is not true, since the surface sand layer does alter microbial activity depending on moisture and aeration conditions.