Creek-Side Soybean Spray with a 50-Foot Aquatic Buffer
You are a licensed commercial applicator in southern Minnesota. A farmer requests a post-emergence treatment on 38 acres of soybean at growth stage V3 for glyphosate-resistant waterhemp. Infestation is in patches covering about 25% of the field; tallest weeds are 6 inches. The label product is a tank mix of fomesafen and clethodim. Label restrictions: 12-hour REI, 45-day PHI for soybean, 50-foot buffer from surface water, no application when wind exceeds 10 mph. Forecast: 9 mph wind from the west, 28°C, 55% RH, no rain for 48 hours. A creek runs along the west edge of the field, 25 feet from the crop edge. A farmstead with a private well is 300 feet west. A neighbor has 12 beehives 0.4 mile northwest. The field is 90 feet from a county road. The applicator has a 200-gallon sprayer with 20-inch nozzle spacing, 15 GPA at 4 mph, and a 60-foot boom. The farmer wants application tomorrow morning. Discuss go/no-go, buffer, nozzle, notification, records.
1. Decide whether to apply tomorrow morning. Explain the key factors and any changes you would require.
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Do not apply as proposed. The wind forecast of 9 mph is inside the label's 10-mph limit but leaves little margin, and the creek is only 25 ft from the crop edge. The label requires a 50-ft buffer from surface water, so the first 25 ft of crop next to the creek cannot be treated at all; if the boom can be shut off on that side, treat only the remainder. A 60-ft boom with 20-inch spacing makes it easy to leave an unsprayed strip, but the applicator must mark it. The private well 300 ft west is outside the buffer, but wind from the west would carry spray toward the field, not the well; still, check the label setback for wells. Beehives 0.4 mile northwest are not directly downwind, but notify the beekeeper if the label requires it. Require: wait for wind 5-8 mph, use air-induction or drift-reducing nozzles, keep boom height low, maintain the 50-ft creek buffer, and avoid spraying if a temperature inversion is present. Also do a jar test for tank-mix compatibility and check clethodim antagonism with fomesafen. If the farmer insists on treating the 25-ft strip, refuse and offer spot treatment or mowing.
2. What recordkeeping and notification steps are required before and after the application?
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Before: confirm the product label, rate, PHI, REI, buffer, and wind restrictions; check the forecast and measure wind at the site; notify the beekeeper if required by label or state law; confirm the location of the well and creek with the farmer; mark the no-spray strip. After: record date, start/end time, field ID and acreage treated, crop and growth stage, product name, EPA registration number, rate per acre, total product used, tank mix order, applicator name and license number, weather including wind speed and direction, temperature, and RH, buffer left, nozzle type, and any deviations. Keep records for the required retention period. Also document any communication with the neighbor and beekeeper. If a spill or drift complaint occurs, record it and follow reporting requirements. Do not rely on memory; the record should let a third party reconstruct why the 25-ft strip was left untreated.
3. If the farmer insists on spraying the entire field including the 25-foot strip next to the creek, how should you respond?
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Refuse. The label's 50-ft buffer from surface water is a legal restriction; applying inside it would be a label violation and could contaminate the creek. Explain the liability: drift or runoff could injure downstream users, fish, and the farmer's own reputation. Offer alternatives: leave a 50-ft no-spray strip and control weeds there with a backpack sprayer using an aquatic-labeled product if allowed, mowing, or cultivation. If the weed pressure in the strip is unacceptable, discuss a different field or a later treatment after consulting the label. Document the refusal and the alternatives offered. If the farmer applies it himself, remind him that he is responsible for label compliance, but do not assist. The judgement call is to protect the resource and your license, not to maximize treated acres.