Getting the most out of an herbicide application not only includes maximizing efficacy, but also minimizing damage caused by herbicides. Being aware of what can go wrong and how to avoid it can lead to effective, on-target herbicide applications and help growers have a successful growing season – without the distress and loss caused by applications gone awry.

Two big threats to herbicide applications are drift and volatilization. While they may seem similar, they are quite unique and require different attention to ensure that neither occur.

Drift

Drift occurs during the herbicide application. It is the unintentional, off-target application of herbicides. This can lead to damage of surrounding crops as well as an ineffective herbicide application. 

There are several factors that can lead to herbicide drift, including: 

• High Wind Speeds: Herbicide labels specify optimal wind conditions for application. If a grower goes off-label, their risk of drift increases. 
• Small Droplet Size: Smaller droplets are more likely to be carried away by the wind than larger droplets. Herbicide labels will also specify optimal droplet size to decrease drift. 
• Severe Temperatures: Ideal temperatures for herbicide-use range from 65 degrees F to 85 degrees F. 

Herbicides are most effective when applied in high humidity and with wind speeds of about 10 mph or less. Ensure that the application nozzles are on the correct setting to produce optimal droplet size to minimize drift. The position and height of the boom are also listed on the herbicide label. With the boom being closer to the crops, the distance the droplets can travel is reduced. 

Volatilization

Volatilization is the movement of herbicide vapors through the air following an herbicide application. Similar to evaporation, volatilization occurs when the herbicide residue changes from a solid or liquid to a gas or vapor. Once vaporized, the vapors can be carried long distances by the wind, possibly damaging surrounding crops as well as causing an ineffective herbicide application. 

The risk of volatilization increases when: 

• Herbicides are applied to inert, non-absorbent surfaces like rocks or pavement, 
• Temperatures are high, 
• Humidity is severe and 
• Herbicide formulations are potentially volatile. 

Reducing the risk of volatilization is vital to have a successful herbicide application. Growers should be sure to avoid unfit conditions including high temperatures and humidity. Identifying if the target has a non-absorbent surface or if the herbicide formulations may be volatile can help growers make proactive decisions regarding tank mixers. 

Drift and volatility reduction agents can help to improve the precise placement of a pesticide spray by increasing the spray droplet size and minimize impact of volatilization of the herbicide applied.

 

Verasure® is an all-in-one adjuvant with a unique combination of functioning agents that improve the performance of glyphosate, dicamba and many other herbicides that require or recommend surfactant, water conditioning, deposition and drift management as well as reducing foam in the spray tank.

• Easy to use, all-in-one adjuvant.
• High-quality drift control without diminishing spray pattern.
• Meets requirements for DRA and VRA in dicamba applications.

The CHS adjuvant lineup is packed with high quality, high-performance formulas to optimize crop protection performance. To learn more about the CHS adjuvant lineup, their ingredients, and their functions, download our adjuvant guide, ‘Using Adjuvants to Improve Crop Protection Performance’. Visit CHSAgronomy.com for full line of CHS adjuvants.