By Leonardo Gottems, Reporter for AgroPages
Revealing how to avoid drift while spraying agrochemicals, Ulisses Antuniassi, member of the experts team from Intacta 2 Xtend Bayer, said, “Among the basic principles of sustainable agriculture, the use of pesticides through the application of inputs in a rational, intelligent and effective way stands out.”
“Some factors can become challenging for a producer in the field, so he must be aware of how to accurately handle them. Drift is an example that can hinder the spraying stage, which is important for crop productivity and yield,” said Antuniassi, a professor at the Department of Rural Engineering at Universidade Estadual Paulista (Unesp).
According to him, drift occurs due to the volatilization of active ingredients or the physical displacement of the drops. “Physical drift is the movement of the drops outside the application area, while steam drift is the movement of the product after the active ingredient is converted of its gaseous form,” he said.
“When it happens, it can cause damage to the susceptible areas around the applications and the reduction of the dose applied in the treatment, reducing the efficiency and inducing the selection of resistant species. Furthermore, drift can generate contamination of the environment and the appearance of illegal product residues in neighboring crops,” he added.
Considering the main factors that cause drift, here are some important tips to reduce risks:
1. Follow the instructions for the product to ensure correct and safe usage, with minimal risk to the environment. Many drift complaints involve the application being different from the instructions on the product package.
2. Select active ingredients or non-volatile or low volatility formulations.
3. If recommended, use adjuvants according to the package inserts. This will result in better efficiency and generally less drift potential.
4. Use tips with a larger orifice size and less spray pressure, preferably models with air induction, producing larger drops with less drift potential.
5. Use the tips at an angle of 110° or higher, keeping the bar stable, level and with a maximum height of 50 cm above the targets.
6. The drift is lower when the average wind speed is between 3 and 10 km/h. Do not spray when there is no wind or during situations in which there may be thermal inversion or convective currents (these meteorological phenomena cause the droplets to fluctuate). Do not spray when the wind is at high speeds (above 10 km/h, on average), or when blowing toward sensitive crops, gardens, homes, livestock, water sources or other sensitive areas.
7. When possible, use lower application speeds. As the speed of the application increases, there are unintended effects on other parameters of the application that can increase the drift.
“The success of the spraying operation depends on several factors. However, two issues are unanimous among experts on the subject: the need to adapt the application technology to weather conditions and adjustments to reduce drift. These two factors are directly related to the application windows (hours available for work). In most cases, the inadequacy of this adjustment can lead to spraying in extreme situations, exposing the system to a greater risk of drift. This fact can cause an unbalanced relationship between quality and safety in applications, which undermines the sustainability of the entire process,” concluded Antuniassi.