Other than wind conditions, what is the most important factor to consider to avoid spray drifting when applying pesticide?

Other than wind conditions, what is the most important factor to consider to avoid spray drifting when applying pesticide?

• A. Temperature
• B. Humidity
• C. Droplet size
• D. Soil density

Answer: (C)

Droplet size is the key factor because it directly governs how long and how far the spray stays airborne. Smaller droplets are light and easily carried by air currents, and they evaporate more quickly, which can leave behind fine, drifting particles. Larger droplets are heavier and settle faster, so they stay closer to the target and reduce drift. So, by choosing nozzle types and settings that produce coarser droplets, you significantly cut drift risk under the same wind conditions. Temperature and humidity do influence drift indirectly—by affecting evaporation and air density—but they don’t control drift as directly as droplet size. Soil density isn’t involved in the spray’s behavior once it’s released into the air.

Droplet size is the key factor because it directly governs how long and how far the spray stays airborne. Smaller droplets are light and easily carried by air currents, and they evaporate more quickly, which can leave behind fine, drifting particles. Larger droplets are heavier and settle faster, so they stay closer to the target and reduce drift. So, by choosing nozzle types and settings that produce coarser droplets, you significantly cut drift risk under the same wind conditions.

Temperature and humidity do influence drift indirectly—by affecting evaporation and air density—but they don’t control drift as directly as droplet size. Soil density isn’t involved in the spray’s behavior once it’s released into the air.