As the planting season approaches, producers are gearing up to apply pesticides. However, before starting your pesticide application there are two important things to keep in mind: pesticide efficacy and spray drift management.
Every pesticide label is different, so it is important for applicators to take the time to read each one carefully before using the product. It is a good idea to check the manufacturer's guide for the right pressure and nozzle combinations too. When you are spraying, using bigger droplets, lower pressure, and keeping the boom closer to the ground can help prevent the spray drift. Remember that higher spray pressures produce smaller droplets that are more likely to drift than larger ones. Additionally, larger droplet size reduces coverage so it may be necessary to increase the carrier rate when spraying. Another consideration is that if you increase the nozzle size you will end up applying higher volumes, but less of it will end up off-target which is good for managing drifts.
Weather conditions play a significant role in determining the success of pesticide applications. Monitoring factors such as humidity, wind speed, and direction are crucial. High wind speeds can lead to spray drift, while minimal wind speeds may indicate the presence of temperature inversion. Temperature inversions occur when solar radiation is no longer strong enough to heat the earth’s surface and the air near the ground gets cooler, trapping the pesticide particles and making it spread where it should not. Temperature inversions typically happen in early mornings and late afternoons. In the morning, clear skies and low wind create favorable conditions for inversions. Signs such as ground fog or dew on plant leaves indicate the onset of an inversion. Similarly, in the afternoon, especially one to three hours before sunset, clear skies and minimal wind increase the likelihood of inversions. Signs such as lingering dust or intensified smells and sounds can serve as indicators of an inversion.
It is also important to be mindful of how pesticide application may impact specialty crops and pollinators in your area. FieldWatch is an online mapping service monitored by Nebraska Department of Agriculture (NDA) that facilitates communication between pesticide applicators, crop producers, and beekeepers. You can visit their website to identify potential sensitive areas before planning a pesticide application. In Nebraska, 710 growers have registered a total of 2,333 specialty crops and apiary sites in FieldWatch. These sites are currently located in 84 of Nebraska’s 93 counties and cover approximately 147,000 acres of specialty crops. You can create an account and map your fields on fieldcheck.org. Registering with FieldWatch is optional and comes at no cost. Pesticide applicators have access to maps, can sign up for email alerts for free, and can download the FieldCheck app or receive direct data feeds. You can go to fieldwatch.com for more information.
You can contact your local extension office for more information on managing pesticide drift or reach out to me at rlamichhane3@unl.edu or 402-274-4755 if you have any questions.
Ritika Lamichhane
Extension Educator
Nemaha County
April 2024