Tips to minimize spray drift

Courtesy of Agriculture and Natural Resources, Univ. of California

Although spray drift is something that will be a constant when it comes to liquid application, it is a problem well within the realm of making more efficient applications. Controlling spray drift not only saves the environment, but can save your pocketbook from retaining precious herbicide.

"Spray drift needs to be minimized to avoid any crop injury and adverse effects on areas outside the spray target area," said Dallas Peterson, Department of Agronomy professor at Kansas State University. "Minimizing spray drift is not only important from and economic and legal standpoint, but also from a public relations standpoint."

Here are some simple tips to keep in mind before heading out into the field:

Wind Speed

"There is no absolute right answer to the question regarding when is it too windy to spray. Labels will provide maximum wind speeds that can't be exceeded to remain in compliance with the label. However, it still may be too windy to safely spray at lower wind speeds if a highly susceptible crops is downwind of the application," said Peterson. "In that situation, the only safe time to spray is when the weed is in the opposite direction. Common sense has to be a major factor in determining when and where it is safe to spray to avoid herbicide drift problems."

Spray Pressure and Spray Speed

The smaller the droplet, the greater odds of creating drift. In addition, smaller droplets are created by higher spray pressures. Pressure shouldn't exceed 40 psi.

"The appropriate spray pressure is critical to produce a good spray pattern and droplet size," said Peterson. Increasing spray pressure reduces spray droplet size and increases the number of fine spray droplet particles that are most susceptible to spray drift. The appropriate spray pressure to optimize performance and minimize drift will depend on the type of spray tip being utilized."

Booms and Nozzles

Position the booms as close to the crop canopy to ensure application reaches the ground. Nozzle tips and pressure is determined by the individual herbicide. Read the label of each chemical to learn proper resistance specifications.

"Spray nozzle selection can have a big impact on the potential for spray drift because of the effect on spray droplet size and spectrum," said Peterson.

Droplet Size

Small microns, 100 to 200 for example, will create a greater risk of spray drift. Larger droplets won't be a susceptible to drift.

"Smaller spray droplets are more susceptible to movement by wind, especially the very fine droplets that can stay suspended longer and moved longer distances," said Peterson.

Prepare for severe weather in the field

Courtesy: Georgia Farm Bureau

Severe weather can pop up in the field with minimal warning, leaving little time to prepare. High winds, severe thunderstorms and tornados are all things farmers need to keep a watchful eye to the sky for while working in their field.

“Thunderstorms can form quite rapidly, within several minutes. Tornados usually come about after strong storms have formed and organized into "supercells". This organizational process can occur over tens of minutes but can sometimes take up to an hour or more,” said Greg Carbin, Warning Coordination Meteorologist for the National Weather Service Storm Prediction Center.

While the central plains of America are nicknamed “Tornado Alley”, these deadly twisters are not limited to any one region. According to the National Oceanic and Atmospheric Administration, the United States average over 1,200 tornados each year. A distant second on the list is Canada, averaging 100 tornados per year. Tornados most commonly form from April to July; however they can occur at any time of year with the right conditions.

“If shelter is unavailable, persons should attempt to move away from the storm. Know where the storms are in relation to your position and be prepared to leave any open area without adequate shelter in the event a tornado is spotted,” said Carbin.

If you find yourself in an open field, stop the machine you’re operating and get out. Lie in a low area or ditch away from the machine. Cover your head and neck with your arms to protect from flying debris. Do not try to outrun a tornado in your machine. A tornado’s speed and direction are deceptive, shifting constantly. Know which buildings near your field can offer the best protection, such as a building with a basement or a sturdy interior space in a barn. It’s important to stay away from the outside walls of the shelter you seek.

While thunderstorms are less destructive, NOAA reports an average of 54 people die in the United States from a lightning strike. Carbin says farmers should watch for increasingly warm, humid and cloudy conditions when anticipating a thunderstorm.

“If lightning is observed, head for better shelter. Lightning will not pose much of threat if you can remain in a vehicle,” said Carbin.

In an open field, find a low spot away from trees, fences, and poles. Make sure the place is not subject to flooding. If you are in the woods, take shelter under shorter trees. If you have no shelter, make yourself the smallest target by squatting low to the ground on the balls of your feet. Minimize contact with the ground, and place your hands on your knees with your head between them when your skin tingles or your hair stands on end. If you are in a tractor or other vehicle during an electrical storm, stay put. Vehicles often provide better protection than lying exposed in open fields.

Have a plan when severe weather is possible. Check weather reports before planning work activities. Make sure you have a way of receiving weather information while you work, especially at remote locations. You can download weather apps for a smart phone or use a weather radio band inside your machine.

“If tornados are expected, then the plan should include more than a vehicle for shelter. Seek a sturdy building and stay away from windows,” said Carbin.