Which soil type allows fumigants to move through it more quickly?

The reason sand is the correct answer is due to its unique particle size and structure. Sand consists of larger particles compared to silt, clay, or loam, which creates larger pore spaces between the particles. This large pore structure allows for greater air and gas permeability, facilitating the rapid movement of fumigants through the soil.

Fumigants need to diffuse through the soil to reach pests effectively, and in sandy soils, this process occurs more quickly because there is less resistance and fewer barriers to gas movement compared to finer soils like clay, which tends to hold water and has much smaller pore spaces that impede gas flow. This permeability of sandy soils is a crucial factor in the efficiency of fumigation treatments.