Fighting Drift On Multiple Fronts
As applicators find more ways to combat spray drift, this season brings plenty of unresolved regulatory issues.
May 6, 2010
Applicators have plenty on their minds when they hit the field for a job. But recently spray drift has been demanding more attention, thanks in part to regulators' and the public's perception of it.
One of the most pressing regulatory challenges for all applicators is EPA's proposed changes to spray drift guidelines listed on labels. They currently say, "Do not apply this product in a way that will contact workers or other persons, either directly or through drift." Industry stakeholders such as the National Association of State Departments of Agriculture had requested clarification on how to interpret and enforce these instructions. A label change released for comment in 2009 stated: "In addition, do not apply this product in a manner that results in spray [or dust] drift that could cause an adverse effect to people or any non-target organism or site."
Does the wording help? Applicators think not. David Eby of Agriflite, Wakarusa, IN, sees the guideline as a "jobs bill for attorneys and additional state employees — investigators. It would have a dramatic chilling effect on pesticide applications with resulting reduced food production." He shared these thoughts with EPA in a letter during the agency's public comment period. Eby and hundreds of other responders have sent input — generating such a strong response EPA may need to delay action. In fact, the original comment period deadline was extended four times and at last check ended March 5. At presstime an EPA spokesperson said staff are still reading and considering comments — and more comment time may yet be added.
Things To Come
Still ahead is closure on a January 2009 court decision (National Cotton Council vs. EPA) that National Pollutant Discharge Elimination System (NPDES) permitting — part of the Clean Water Act — be required for ag pesticide applicators. The regulations call for permits to apply products on, over, or near water sources. CropLife America and other industry groups argue that these applications are already effectively regulated by EPA under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA).
The U.S. Supreme Court was petitioned to review the ruling but refused. The final decision by the 6th Circuit Court of Appeals is stayed until April 2011.
Retailers and applicators used words like "disaster" and "nightmare" when asked about the prospect of getting NPDES permits. "The process is ignoring FIFRA and what it stands for," says aerial applicator Schertz.
Brian Rau of Medina Flying Service, Medina, ND, notes that the word "near" in "near water" has not been clarified so far by EPA and will be a problem. "There's always the concern some entity will attempt to use the word to cause trouble, limit application, or litigate," Rau says.
Eby also believes it is unfair that applicators are unjustly targeted and held solely responsible in drift claims, when manufacturers, EPA, crop advisors, and growers all play a role.
Jason Paris, crop protection department head at MFA Inc., Columbia, MO, believes every retailer needs to be involved in state or industry associations to stay abreast of new regulations — and to help educate those in charge of creating these new laws. "And we have to make sure we are good stewards on our own without any more pressure from EPA."
Some retailers admit feeling pressure from other sources, including state regulatory agencies. One such case: This spring, Landmark Agronomy was called to Madison, WI, to meet with state Department of Agriculture, Trade, and Consumer Protection (DATCP) officials. The regulators presented a complaint from a grower-customer's neighbor that a Landmark 2,4-D application had damaged a line of oak trees.
Landmark's team ran through its own multi-faceted investigation of the incident. "Everything we did was just spot-on, we couldn't have done the application more perfect," says Landmark's Jim Shelton. For example, winds actually blew away from the trees in question, and wind speed clocked in below label guidelines. Drift reduction nozzles were used in combination with a drift retardant to further protect the field's surroundings.
Ultimately, DATCP found problems in its own case that day — including the discovery that the grower himself had sprayed a growth regulator with a similar mode of action to 2,4-D just about a week before damage appeared. Landmark's application had occurred a month before. A final ruling is still pending.
Shelton says his company has taken an aggressive stance against drift since the advent of Roundup Ready soybeans in the late 1990s. "We have pretty much made drift retardants mandatory with all Roundup/glyphosate applications," he says. In fact, drift retardants are used with many products.
Some cost-conscious growers hesitate to spend the extra money (about $1 to $1.50 per acre) for retardants, but if a customer demands that Landmark not use one, he has to sign a release. If a drift event occurs, the grower must take total responsibility for it, including damages and any fines from DATCP.
"Sales of deposition products or products containing deposition aids have increased dramatically over the last several years," reports MFA Inc.' Paris.
Todd Kautzman, owner, Mott Grain Co., Mott, ND, swears by drift retardants, noting: "We've never sprayed an acre without one." The company treats some 50,000 to 60,000 acres a year of small grains, including wheat, canola, and flax, using Coverage G-20 and In-Place. Kautzman has found the products can make up for less-than-ideal conditions, provide drift control, and get "more chemical on the plant."
He doesn't even ask customers if they want a drift retardant. "We don't bill the customer for it. It's insurance for us," he explains. But Kautzman finds it easy to convince customers of the value of retardants, showing videos and photos — some shot on windy days — of the products' efficacy to growers at company meetings. And his operators, skeptical at first about the technology, now "won't even get into my equipment and spray unless they can use a drift retardant."
And some large advances have come in sprayer nozzle design over the last few years. Shelton says Landmark selects nozzle types that reduce drift, including air induction nozzles. Air inclusion, air induction, or venturi nozzles are flat fan nozzles where an internal venturi creates negative pressure inside the nozzle body, explains Andrew Landers, pesticide application technology specialist, Cornell University. "Air is drawn into the nozzle through one or two holes in the nozzle side, mixing with the spray liquid. The emitted spray contains large droplets filled with air bubbles (similar to a candy malt ball) and virtually no fine, drift-prone droplets," says Landers. He adds that the droplets explode on impact with leaves and can produce similar coverage to conventional, finer sprays.
Kautzman used air induction nozzles some four or five years ago, even putting on demonstrations and promoting them before drift retardants came on the scene. Now he has mixed feelings. "These nozzles are excellent for drift control, but what we found was that in order to reduce drift, they produce a larger droplet — which is harder to blow away — but the problem with that is in a lot of cases, we didn't get the chemical coverage on the plant," he says. "We saw a reduction in control or effectiveness of the product we used."
Kautzman has had the most success with a very good stainless steel flat fan nozzle, with product running through at 30 to 40 pounds of pressure to reduce drift. He says an air induction tip calls for 60 to 90 pounds of pressure, which can also present coverage problems.
Aerial applicator Mike Lee, Earl's Flying Service, Steele, MO, says his company has changed spray tips on its airplanes — to a bigger tip and fewer nozzles per plane. "The larger tip is safer and more efficient," he's found.
"Our firm has slowly used large and larger droplet spectrums," says Mike Schiffer, Al's Aerial Spraying, Ovid, MI. He points out that with an adequate volume of carrier, the larger drops ensure more of the material is placed on the intended crop. "That helps provide the coverage lost by using larger drops, and it means less product drift," he says.
Many aerial applicators have developed their own innovations to reduce drift. Agriflite's Eby designed his own spray tips and check valves several years ago. Sold under the AeroFlow brand name, they've become some of the most commonly used in the industry.
JR Reabe of Reabe Spraying Service Inc., Plover, WI, has adopted an idea out of Australia that allows pilots to change from a coarse droplet spectrum to a medium or fine droplet spectrum and back while in flight. "This allows us to use coarse droplets on a drift-sensitive edge of a field, but use finer droplets on the rest of the field," explains Reabe.
A huge part of preventing drift damage is simply knowing where product shouldn't go. A new tool for communicating this is the Driftwatch Web site (www.driftwatch.org), developed by Purdue University. In Indiana, growers of sensitive crops — as well as managers of sensitive habitats — register their acreage on the site, then pesticide applicators can easily locate them using a Google Maps interface. Cost for ramping up a state's page is just $25,000, and EPA is already putting money into the project.
Driftwatch maps are incorporated into AgSync, a new online software concept developed by Eby and supported by BASF. The product allows applicators to create a shape file of the field to be sprayed, then the shape file boundary is imported to a GPS computer. The applicator is then alerted to a sensitive area prior to spraying, allowing time to modify plans. It is currently being used in 15 states.
Scott Schertz, Schertz Aerial, Hudson, IL, is using new mapping technology to put known or suspected drift-sensitive sites on a base map, so "it does not matter who prepares the map, problem areas won't slip through anyone's attention." He notes that such improvements come at a cost. "The overhead for this business has at least tripled. It takes lots of staff time to mark maps and coordinate activities," he says.
Michigan's Schiffer is happy that on-board weather data is now a reality, thanks to systems that measure and record wind speed, wind direction, humidity, and temperature. Coupled with DGPS, his computer can create models predicting droplet movement — then plot aircraft flight accordingly.