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Application Record Keeping: A Protocol for Documenting the Weather

One of the new requirements for the application of XtendiMax, FeXapan, and Engenia will be for applicators to keep records for each application.  Applicators are always expected to be good stewards when applying crop protection products, especially with these dicamba based products.  With a major emphasis on avoiding spray drift into sensitive areas, a critical part of keeping good records includes accurately recording the environmental data associated with each application.  A document has been developed to help applicators establish a protocol for recording consistant and accurate weather records.  Use the following link to access that document.

Application Record Keeping: Focus on Environmental Conditions

A recent visual inspection of venturi nozzles used at low pressure in combination with a DRA reveals that several nozzles on the dicamba 'approved list' may not provide a suitable pattern that could effect coverage, which may also result in poor weed control.  Review the information reported at this link.

Pattern Quality Issues


The EPA recently issued revised labels for XtendiMax w/VGT, FeXapan wVGT, and Engenia.  As in 2017, these labels have specific requirements on certain sprayer operation parameters.  For instance, each label specifies a minimum GPA (ExtendiMax and FeXapan at 15 GPA and Engenia remains at 10 GPA), a maximum travel speed of 15 MPH, and also suggests or recommends adhering to the pressure ranges specified by the nozzle manufacturers for the nozzle type selected.  The original nozzle approved by the EPA, the TTI10004, was based on using the TTI11004 at a maximum operating pressure (63 psi for XtendiMax and though not listed, similar for Engenia).  The approval was based on wind tunnel testing with the droplet data entered into the AGDISP Model for the purpose of creating a drift profile.  That drift profile was then used to compare various combinations of the above dicamba products with all tank mixes including DRA's and nozzles.  In order to become approved for use, all nozzles, chemistries, and DRA's must be equal to or less than the drift profile level origianlly established for the TTI11004..  

In order to help applicators (those making decisions) and spray machine operators understand what limitations these specifications place on making applications to DT crops, I have completed a document with charts showing the math for the various options that would be possible.  Speed and pressure are typically used to determine the operating parameters for any give application scenario.  That will not change, but because of the restrictions on the label, the flexibility in making the applications will be severely limited for each combination of parameters.  This is particularly true when using conventional spray systems equipped with rate controllers.  The information included in the charts does not include PWM sprayers.

The charts will show the results of the calibration math for the GPA, MPH, and PSI options.  The calculations are for any of the approved nozzle orifice sizes (03, 04, 05, 06) and are based on 15 and 20-inch nozzle spacings.  The results will be different for each nozzle spacing. The formulas used to determine GPM and PSI are footnoted in the document.  The acceptable combinations are based on a pressure range considered appropriate (by the author) or otherwise specified in the label.  For most of the venturi nozzle types, I am using a pressure range of 40 - 65 psi (exceptions are noted).  The charts reflect speeds from below 10 MPH and at a maximum of 15 MPH.  The range for the GPA options range between 10 and 20 GPA.

The nozzle charts available on the above product websites suggests that using low operating pressures are acceptable.  I have a concern regarding the lower range of the pressures that are published with these on-line approved nozzles,  It is possible for venturi nozzle designs at lower pressures to have a poor pattern and also too large a droplet.  Sure that meets the EPA to mitigate drift, but using at low pressures may end up with inadequate coverage on the target, reducing the effective of the application.  To me that will not be good for the success of these herbicide technologies.

Using the University of Illinois Smart Phone or Tablet App - SPRAYER CALIBRATION CALCULATOR, is a very efficient way to complete all the necessary calculations for this table or any other similar calibrations needs such as this.  This app is available through Google Play or the App Store on your phone or tablet.

Links to charts:

20-inch nozzle spacing - MPH and PSI Options when Applying XtendiMax, FeXapan, and Engenia

15-inch nozzle spacing - MPH and PSI Options when Applying XtendiMax, FeXapan, and Engenia - not available at this time.



The EPA has approved the 'over the crop' use of Xtendimax w/VGT, Engenia, and Enlist Duo w/Colex-D as a technology to help control resistant weeds in herbicide tolerant cropping systems.  As expected, in states where these products will be used, special rules are being developed regarding how these applications will be made.


The recent EPA approvals of XtendiMax w/VGT (Monsanto), FeXapan w/VGT (Dupont), Engenia (BASF), and the earlier approval for Enlist Duo w/Colex-D (DAS) have presented new challenges for the application industry.  Spray system operators will now be required to adhere to some very detailed specifications regarding the setup and operation of the sprayers used to apply these products.  This has not always been the case in years past.  Labels of the future are expected to take on this new format.  Especially, as we enter into an era of applying crop protection products designed for making applications to herbicide tolerant crops for the purpose of controlling resistant weeds.  For example, in the three crop protection products listed above; nozzle type and size, pressure, droplet size, ground speed, and spray boom height, are among some of the parameters that are specified.

It will be paramount that all involved in the application decision making process read, understand, and follow the current version of the label before making any applications. Nothing has changed, the label is a legal document, and must be followed in order to safeguard the availabilty of these new chemical technologies.

 A chart contrasting and comparing the specified application parameters for these products has been prepared to help make sound decisions regarding their application.  The information provided in this chart is based on the instructions contained in each label, the authors interpretation of those instructions, and also contains editorial comments from the author.  The comments are to further emphasize proven application strategies and practices to ensure good stewardship while making successful applications.  Use this link to access this document.

Application Comparison Chart - Version 6

Pollinator Protection

Pesticide risk management must be based on sound science, consistent with the laws under which pesticides are regulated in the United States. EPA has been working aggressively to protect bees and other pollinators from pesticide exposure.  Proposing a plan to prohibit the use of pesticides that are toxic to bees when crops are in bloom and bees are under contract for pollination services. The plan also recommends that states and tribes develop pollinator protection plans and best management practices. For more information on steps to protect pollinators, link to this EPA site.

Additional information on State pollinator protection plans and pollinator health reports can be found on the following website.  Pollinator Stewadship Council.

Information regarding pollinator protection is also available through FieldWatch/DriftWatch. The BeeCheck program is a voluntary communication tool that enables beekeepers and pesticide applicators to work together to protect apiaries through use of the BeeCheck mapping program. Likewise, pesticide applicators utilize the site to help determine the location of specialty crops and beehives in their trade areas. DriftWatch and BeeCheck provides the platform to facilitate better awareness, communication and interaction between all parties as one part of ongoing stewardship activities.


EPA Worker Protection Standard Revisions

Worker Protection Standard: EPA's Agricultural Worker Protection Standard (WPS) is aimed at reducing the risk of pesticide poisoning and injury among agricultural workers and pesticide handlers. The WPS offers occupational protections to over 2 million agricultural workers (people involved in the production of agricultural plants) and pesticide handlers (people who mix, load, or apply crop pesticides) who work at over 600,000 agricultural establishments (farms, forests, nurseries and greenhouses).  For more details, use the link above.

WPS Revisions:  EPA is announcing stronger protections for the nation’s two million agricultural workers and their families working on farms, forests, nurseries, and greenhouses. These revisions to the 1992 Agricultural Worker Protection Standard will afford farmworkers similar health protections that are already afforded to workers in other industries.  For more details, use the link above.

Application Exclusion Zone:  A major addition to this revision is the Application Exclusion Zone (AEZ).  New no-entry application-exclusion zones up to 100 feet surrounding pesticide application equipment will protect workers and others from exposure to pesticide overspray.  This will be based on the ASABE S-572.1 for classifying spray droplet sizes.  Refer to the above link for additional details.

WPS Train-the-Trainer Criteria and Process:  EPA’s revised Worker Protection Standard (WPS) was published as a final rule on November 2, 2015.  The 2015 revision requires persons seeking to become trainers of workers and handlers through completing a Train-the-Trainer program to qualify by completing an EPA-approved Train-the-Trainer (TTT) program. This requirement becomes effective on January 2, 2017, meaning that a person must complete an EPA-approved program before that date to qualify as a WPS pesticide safety trainer for workers and/or handlers. EPA has prepared guidance material to facilitate the development of programs that meet EPA requirements.  The above link will take you to the EPA guidance document.


FieldWatch is a non-profit company that offers mapping and communication tools which are just one element of a successful formula for successful co-existence of specialty producers, large scale commodity farmers, commercial and private applicators and beekeepers.  Communication is the start, but cooperation and collaboration of all parties is essential.  Sometimes it means compromise or adjustments that foster an environment that everyone can do what they need to do with respect to the needs of others.

The DriftWatch-Registries site is a voluntary communication tool that enables crop producers, beekeepers, and pesticide applicators to work together to protect specialty crops and apiaries through use of mapping programs. It is not a substitute for any state regulatory requirements.  With DriftWatch, producers of high-value specialty crops, such as tomatoes, fruit trees, grapes and vegetables, register their sites on-line and provide contact information about their operation. With BeeCheck, beekeepers register their hives on-line and provide contact information.  Likewise, pesticide applicators utilize the site to help determine the location of specialty crops and beehives in their trade areas. DriftWatch and BeeCheck provides the platform to facilitate better awareness, communication and interaction between all parties as one part of ongoing stewardship activities.

Drift Reduction Technology - DRT

Drift Reduction Technology Program Description:

The EPA's purpose for the Drift Reduction Technology (DRT) Program is to encourage the manufacture, marketing, and use of spray technologies scientifically verified to significantly reduce pesticide drift. Initially, the focus of the program is on spray technologies used primarily for pesticide applications to row and field crops by ground or aerial application equipment. Plans to expand this program to include technologies for orchard and vineyard crops are being considered.

To participate, technology manufacturers are encouraged to test their technologies for drift reduction potential. Test protocols have been provided to guide these evaluations.

Technologies include but are not limited to:

• Nozzles
• Spray shields
• Drift reducing adjuvants with adjuvants defined as any substance separately added to a pesticide product (typically as part of a spray tank mixture), that will improve the performance of the pesticide product.

The EPA will use a rating system to indicate the level of potential drift reduction of tested technologies. Based on review of submitted test results, a DRT rating will be assigned, using one to four stars, to each technology that meets the minimum standard for drift reduction. Pesticide manufacturers will be encouraged to state on their product labels that applicators should use DRT-rated technologies in applying pesticide products.

Benefits of Using Drift Reduction Technology:

Using DRT-verified pesticide spray technology can benefit pesticide applicators, the environment and people by:

• reducing loss of pesticide from the application site,
• keeping more of the applied pesticide on the crop, improving pest control,
• reducing pesticide exposures to people, wildlife, and the environment, and
• reducing risks of damage and liabilities from off-target deposition of drift.

The use of DRTs should result in significantly less pesticide from spray applications drifting and being deposited in areas not targeted by those applications, compared to spray technologies that do not meet the minimum DRT standard. As a result the EPA may place fewer use restrictions on pesticide products that must be used in conjunction with DRTs.