UREA...How volatile, how much N loss?

Tree Spud

5 year old buck +
My understanding is that UREA has a short shelf life when spread and needs to be rained on withing 48 hours to avoid losing the N during to vaporization. That makes it tough to use when you primarily only have weekends to work with.

I have seen some with more knowledge on the topic comment on how critical is rain timing and losses. Would like to get some feedback.
 
A lot of guys won't use it without it being treated with Agrotain or a generic version. I think that'll buy you about 2 weeks. Is that an option? And it's best if you get a good soaking rain. I wouldn't be spreading it if there's a 30% chance of a quarter inch.
 
If you don’t get rain within 3-4 days you will lose 20-40% the the N due to volatility. There are products that stop or slow down the volatility. The most common one is Uflexx and Umaxx. They are urea that have been treated with denitrifying agents that keep them from volitization . They also work as a slow release because they keep the soil from turning the urea into a useable form of N .
 
^^^^ Good thoughts on both above, i will have to check with my feed mill if it is treated.

I am an avid fan of weather.com in trying to plan for spreading when good rain is forecast, their record of accuracy is not that good though.
 
I generally try to top-dress Urea when we are expecting at least 0.5" of rain, however, I have had the Urea completely dissolve with as little as 0.2" of rain in my rain gauge following application.

"The worst way is to apply urea on the soil surface without incorporating it with tillage or irrigation, have hot temperatures and not have rain within three to four days after application. If you have all these things happen, you can have urea losses of up to 40 percent, but 20 percent losses are more common. A key to remember is that ALL three things have to happen for the urea losses to occur. If you till in the urea within three to four days, or irrigate it into the soil within that time frame, or have rainfall within that time frame, or it is cool (less than 70° F sustained), urea losses will be insignificant."


The above quote can be found in this link:

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=12&cad=rja&uact=8&ved=2ahUKEwjUqdHnirniAhVEu54KHcVpABwQFjALegQICBAB&url=https://www.noble.org/news/publications/ag-news-and-views/2009/may/nitrogen-losses-from-urea/&usg=AOvVaw2CW6Gxe3ejgme3_XVls_CJ
 
NOT losing urea based nitrogen is more common than the opposite. Otherwise, the product would cease to be a viable economic alternative. Coated urea and urea - ammonium sulfate blends are "expensive" alternatives where N loss is a realistic concern. We don't talk about it, but other N fertilizers can be lost thru other soil structure issues. Think about that.
 
Top