The 2026 Dicamba Label Changed What You Have to Record. Here's What That Means at the Nozzle.

EPA approved new over-the-top dicamba registrations for the 2026 and 2027 growing seasons - Engenia, Tavium, and Bayer's dicamba product (XtendiMax's replacement, now labeled Stryax) -and called them the most restrictive dicamba labels in the agency's history. Most of the attention has gone to the new buffer distances and temperature cutoffs. The part that affects every single application, whether or not anything ever drifts, is the record-keeping requirement.

What the label actually makes you record

For every dicamba pass, you must measure and log wind speed, wind direction, and air temperature at boom height, in the field, at the start of the application, at the end of the application, and at every tank refill in between. That's not a weather-app reading from town; you have to take it where the boom is, at the moment you're spraying. Screenshots or printouts of weather at the time of application are required.

A state pesticide regulator can cite an applicator for incomplete records even when a drift complaint never comes up; the paperwork is the compliance, not just evidence if something goes wrong.

The conditions you're recording against

The 2026 label pairs that record-keeping requirement with a tighter operating window than before:

• Wind speed between 3–10 mph while using coarse or coarser spray droplets.
• Mandatory Drift Reduction Agent (DRA) is required in every tank.
• No application allowed when dicamba-sensitive crops are downwind.
• No application during a temperature inversion
• No application within 48 hours of forecast rain, or on saturated soil
• No application within 1 hour after sunrise or within two hours before sunset
• No application if the forecast high is above 95°F that day or the next; between 85–95°F, only half of a grower's dicamba-tolerant acres per county can be treated in a day
• A 240-ft downwind buffer, reducible only with label-approved mitigation

Every one of those thresholds depends on the same boom-height reading you're already required to log.

Why the reading and the record have to be from the same instrument

If your wind reading comes from one source and your logged record comes from writing a number down later from memory, that's a gap a compliance review will find. A meter that measures wind speed, direction, and temperature at the nozzle and logs it with a timestamp closes that gap in one step. The Kestrel 3550AG Weather Meter for Spray Applications and 5500AG Agriculture Weather Meter do this over Bluetooth to the free Kestrel LiNK app, which keeps a running, exportable, shareable record - the same report you'd hand over if a state inspector or your ag retailer's compliance team asked for it.

Where Delta-T and drought stress still matter

Wind and temperature aren't the whole story. Delta-T - the gap between dry bulb and wet bulb temperature, which the 5500AG calculates on the spot - tells you how fast your droplets will evaporate, which matters for coverage and drift risk on every foliar pass, not just dicamba. And with drought stress elevated across much of this year's corn, soybean, and wheat belt, there's less room for a bad pass on an already-stressed field heading into late-season fungicide, desiccant, and harvest-aid applications.

Which Kestrel Meter fits your operation

Both the 3550AG and 5500AG take the boom-height wind, direction, and temperature readings the dicamba label requires and log them the same way over Bluetooth - the difference is how much additional decision-making data you need alongside that compliance record.

The 3550AG is the right fit for private applicators and smaller operations spraying their own acres, where the priority is a compact, affordable meter that covers wind speed and direction, temperature, and humidity, satisfies the record-keeping requirement, and is easy to keep in a shirt pocket or cab door for a quick check before every pass.

The 5500AG is built for commercial and custom applicators, co-op agronomists, and larger operations spraying across multiple crops and products beyond dicamba. Alongside the same boom-height readings, it adds Delta-T and Temperature-Humidity Index (THI), so the same device that satisfies your record-keeping is also making the nozzle, timing, and drift-risk call on fungicide, insecticide, and harvest-aid passes where evaporation rate matters as much as wind.

If dicamba compliance is the main job, the 3550AG covers it. If you're making spray-timing decisions across a full program all season, the 5500AG's added readings earn their keep.

FAQ

What does the 2026 dicamba label require applicators to record?

Wind speed, wind direction, and air temperature measured at boom height in the field, recorded at the start of the application, the end of the application, and at each tank refill. For an in-depth description of the requirements, please visit https://www.epa.gov/ingredients-used-pesticide-products/registration-dicamba-use-dicamba-tolerant-crops

Can I use a weather app instead of a handheld meter for dicamba record-keeping?

No. The label requires an in-field, boom-height measurement. Most weather apps and nearby stations report conditions at standard heights and locations that don't reflect what's happening at the boom, and don't satisfy the label's requirement.

What wind speed range is allowed for dicamba applications?

3–10 mph. Applications are also barred during temperature inversions, within 48 hours of forecast rain, on saturated soil, within 1 hour after sunrise or within two hours before sunset, and above certain temperature thresholds.

Is dicamba record-keeping required even if there's no drift complaint?

Yes. It's a standalone label requirement enforced by state lead agencies, independent of whether an off-target movement incident ever occurs.

What is Delta-T and why does it matter for spraying?

Delta-T is the difference between dry bulb and wet bulb temperature, and it indicates how quickly spray droplets will evaporate. A high Delta-T increases drift risk because droplets stay airborne longer; a low Delta-T can mean poor spray drying and runoff.

What's the difference between the Kestrel 3550AG and 5500AG?

The 3550AG is a compact, Bluetooth-enabled meter covering wind speed and direction, temperature, and humidity. The 5500AG adds Delta-T and Temperature-Humidity Index (THI) calculations for a more complete read on spray timing and drift risk.