Minimizing toxic effects of pesticides on pollinators
"In both pesticide products, the labels stated 'high toxicity' on bees. In figure 1, the label proceeds with the direction not to apply the product if bees are visiting the treatment area. In figure 2, the product is not to be applied while bees are actively visiting the treatment area. The subtle difference between 'visiting' and 'actively visiting' has quite a large significance," he said.
In this case both pesticides are toxic to bees but, Hadi explained, the pesticide in figure 1 has an extended residual toxicity compared to the pesticide in figure 2. Consequently, the product in figure 1 has a longer toxic period against bees compared to the one in figure 2.
"The phrase "do not apply if bees are visiting," in figure 1 signifies the product's potential to kill bees by residual effect. In this case, bees visiting treated areas later during the day can still be fatally affected by the product,'" Hadi said. "In the case of the product in figure 2, the phrase 'do not apply while bees are actively visiting' signifies the product's potential to kill bees in the case of direct exposure."
Practically speaking, Hadi said the product in figure 2 should not be used when the bees are visibly foraging in the field.
"During crops' blooming period it is recommended to use pesticides with label language illustrated in figure 2," he said.
Keeping in mind, Hadi said, that application of the product in figure 2 should be conducted after the active foraging time for bee is completed - for example in the late afternoon or in the evening.