Zero-tillage systems require timely pesticide applications to control weeds & diseases. A southern Alberta farmer tried spraying at night and had some success. Farming Smarter wanted to find if night spraying could provide a feasible alternative to poor daytime conditions and potentially improve efficacy due to greater absorption. Night spraying might provide farmers with the option to cover the same acres in a shorter time frame or to cover more acres with the same equipment.
In preseed burndown (PSBD) trials, plots were sprayed at label-recommended and three quarter-label rates with four herbicides: Prepass (Florasulam), Rounndup (Glyphosate), Aim (Carfentrazone) and Heat (Saflufenacil) according to the experimental design using hand held sprayers equipped with two meter booms and CO2 propellant at three different timings, day (12-2 pm), night (12-1 am) and early morning (4-5 am).
In-crop trials plots were sprayed at three quarter-label rate with the herbicides, Liberty (Glufosinate-ammonium), TM Muster + Select (Ethametsulfuron-methyl + Clethodim), Vantage™ Plus MAX II (glyphosate), Odyssey (Imazamox, Imazethapyr), Select (Clethodim), OcTTain (fluroxypyr, 2,4-D LV ester), Everest (Flucarbazone-sodium), Axial + Infinity (Pinoxaden + Prasulfotole, bromoxynil) and Barricade (Thifensulfuron, methyl, tribenuron methyl) depending on the target crop and experimental design, using similar equipment and spray timing as mentioned above in the PSBD trials.
Project technicians actually got out at midnight to test the theory.
Night Spraying Herbicide Report
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