Most phytotoxicity to non-target plants is the result of drift.

• A. Runoff
• B. Leaching
• C. Drift
• D. Fracking

Answer: (C)

Pesticide drift is the off-target movement of sprayed chemical through the air, and this is why it most often causes phytotoxicity in nearby non-target plants. When droplets are fine or weather conditions allow the spray to travel with the wind, these particles can land on adjacent crops, ornamentals, or vegetation not intended for treatment. The resulting residue can injure leaves, cause bleaching or browning, curling, or stunted growth in those plants, even though the application was aimed elsewhere.

Other pathways, like runoff, require rain or irrigation to push the pesticide off surfaces, moving it with water rather than through the air to nearby plants. Leaching moves chemicals downward through soil toward groundwater, which typically doesn’t produce immediate above-ground injury to neighboring plants. Fracking isn’t related to how pesticides move in the environment. To reduce drift, use appropriate nozzle types and pressures, favor larger droplets when feasible, spray under favorable weather conditions, and establish buffer zones.