Tom Wolf, co-founder of Sprayers 101 and a 35-year spray application researcher, joined Dan Aberhart and Darren Sander of Crop-Aid Nutrition to work through three things Prairie operators should check before the spraying window gets away from them: water quality, coverage, and sprayer productivity. The conversation opened with Tom's line from the prep call -- "doing the right thing at the right time; take away the right time part and the right thing is irrelevant" -- and held that frame for the full hour. Farmer contributors Jeff Bennett and Jay Peterson brought real water test results and operational questions into the session live, making the five-number water quality framework immediately applicable. What came through clearly is that most spray misses are not careless -- they are caused by tighter windows, more complex tank mixes, and a series of small time losses that add up to a quarter section of capacity gone.
Tom Wolf opened with the frame that carried the session: doing the right thing at the right time. Take away the right time part and the right thing is irrelevant. Spraying has changed dramatically -- operators who used to make two passes a year now make three to five, and the equipment cost running at roughly $400 an hour means every minute away from spraying is measurable. The first section covered water quality, built around five numbers from a standard water test. Darren Sander opened with the operator's version of the lesson: Crop-Aid's farm pulls from a cold well at 1,200 TDS, so they tank it into black poly storage and spray from the warmest tank first. Cold water hurts efficacy -- especially glufosinate. Tom then walked through pH (most mixes fine; what matters is the final mix pH, not source pH), TDS and conductivity (under 500 is clean; most Prairie wells come in over 1,000; the number tells you whether to look further), bicarbonates (500 ppm is the threshold; above it, ammonium sulfate is the most versatile fix), total hardness (calcium carbonate equivalent; Jeff Bennett's water had very low hardness but elevated sodium, which still antagonizes glyphosate and glufosinate), and turbidity (aluminum sulfate as a flocculant for dugouts; stir and leave 24 to 48 hours). Jeff's live water test from Agvise became the worked example. Tom's verdict: low hardness, elevated sodium, ammonium sulfate recommended.
The coverage section opened with a number that reframed the whole conversation: according to a Mesonet researcher in North Dakota, 100 percent of nights in the state experience thermal inversions. Some are worse than others, but the baseline is total. Under an inversion, fine droplets go where they want -- downhill if there is topography, anywhere if there is not. Tom's prescription: start on the downwind side of the field, spray perpendicular to the wind, turn into the headwind on every pass. Never spray down and then back against the wind. The droplet size discussion followed: coarser nozzles, deployed early in Canada before most countries, allowed operators to spray in slightly windier conditions without adding drift risk. Air induction tips are the go-to for general spraying. Spray pressure -- as low as 30 psi for AI tips -- adjusts droplet size one category in either direction. Water sensitive paper laid on the ground is the cheapest coverage check available. On water volume, Tom's position was direct: more is better. Complex tank mixes behave better with more water. More water allows coarser droplets without losing coverage. Later-season applications -- PGRs, fungicides, desiccants -- want 10 to 15 gallons per acre. Cutting back on water to improve logistics is a trade with a real cost.
The logistics section brought Jay Peterson into the conversation. He runs a 1,600-gallon machine with a 120-foot boom and a dedicated water truck driver. His fill times on easy mixes: seven to nine minutes on three-inch plumbing. Complex mixes with dry products that need to hydrate: 15 minutes. Tom confirmed those numbers are right. The tendering revolution changed spraying fundamentally: a 30-minute fill is now a five-minute fill, which means filling is the stressful moment and spraying is the calm one. Continuous rinsing systems collapsed a three-quarter-hour triple rinse down to five minutes. Tom's recommended exercise: when the sprayer engine is running, write down what you're doing if you're not spraying. Data entry, monitor troubleshooting, looking for a menu -- every one of those is a round you did not spray. The session closed on the same line it opened with: an important job is worth doing well.
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