Wheat School: How to avoid leaf burn from UAN

[@lovetofly32]

Man Im the 6th viewer! 😄 Our wheat is heading out here in kansas. Looks gooood!😁

[@oldfartonabmx2122]

So your UAN over there is 28%? Ours here in Australia is about 42. No wonder I burned our wheat! And it sounds like your intention is to not get any on leaf - no leaf absorption? I’ve been trying for leaf absorption. 👍

[@WheatPete]

We dilute UAN to 28% so it does not salt out under cold temperatures. My guess is your UAN is 32%, I believe that is as high as you can get into solution. We use 32% UAN in season when it won't be stored over winter. Spraying straight 28% or 32% right on the leaf with fine droplets (herbicide nozzles) will definitely burn the leaves. Very little N is absorbed through the leaf regardless, roots have evolved to take up N, not leaves. Even when a safer N source is applied in a foliar application, at least 90% is washed off the leaves and taken up by the roots in most studies that have looked at this.

[@oldfartonabmx2122]

@@WheatPete thanks. EasyN is 42.5% total N. 👍

[@WheatPete]

@@oldfartonabmx2122 Brochure shows 42.5% weight per volume. 32% weight per weight. 32% is all that can dissolve on a weight per weight basis. Fertilizer nitrogen is always reported on a weight per weight basis here. Not sure in Australia.

[@oldfartonabmx2122]

@@WheatPete yeah it’s weight volume

[@oldfartonabmx2122]

@@WheatPete I see now, 42% w/v, 32%w/w.

[@Boostertee]

Watching from Zimbabwe, my wheat now at tillering stage.....

[@wholelover]

Even after splitting nitrogen, i got the dreaded burns. But i saw the weeds were dead, finished, and the wheat couldn't look better in terms of yield potential