Wheat School: Think droplet size for fusarium fungicides


Will nozzle type solve the problem of getting efficacy while spraying T3 fungicides? There’s plenty of work done on the right nozzle for this job, but what are the other factors that lead to an efficacious application for controlling fusarium?

In this Wheat School episode, our resident agronomist Peter “Wheat Pete” Johnson is fired up and has some insight into what to pay attention to, when it comes to spraying T3 fungicides.

First up is droplet size. Why do turbo floodjets do a better job than forward/back nozzles? Because they have a coarse droplet size, says Johnson. A coarse droplet will go farther than a fine droplet. Not only does the droplet need to reach the wheat head, it needs to also reach the front and back of the wheat head.

“We don’t think we want ultra-coarse or extra-coarse, because then we don’t have enough droplets to hit the head,” says Johnson. Further to that, fogging it on will do a really good job of “painting” only one side of the head, which is only 50 per cent efficacious, at the very best.

Check out the video for Johnson’s nozzle recommendation, his thoughts on anti-drift agents, and a good analogy on droplet size, story continues below:

Spraying straight down at the correct angle will reduce the distance the droplets need to travel. Lowering the boom 10 to 12 inches off the canopy, which also means reducing speed and fill time to get the same amount of acres done in a day.

The last thing to think about is windy conditions, says Johnson. “If you’re in windy conditions, and we typically talk about 10 kilometre an hour winds, but if you think about throwing that coarse droplet, if you’re throwing it into a gale force wind, the wind’s going to win,” says Johnson.

Of course, the right nozzles are important, but carefully consider all these other factors when spraying T3 fungicides.

Wake up with RealAgriculture

Subscribe to our daily newsletters to keep you up-to-date with our latest coverage every morning.

Wake up with RealAgriculture

Other Episodes

Wheat School (view all)Season 12 (2021) Episode 19

Please register to read and comment.


Register for a RealAgriculture account to manage your Shortcut menu instead of the default.