Posted 1/10/2019 10:52 (#7234711) Subject: Fall NH3 vs Fall UREA
I posted a fall nh3 vs fall injected urea test result a couple of weeks ago. Since then I have been getting a lot of questions as to why the urea is consistently out-performing the nh3 in our tests. Instead of continuing to answer individually, I thought I would post our theory on the reason behind the results.
We treat both UREA and nh3 with n-serve in our test plots. We do this because we have found through earlier testing that fall applied urea without n-serve does not work. The reason that fall applied nh3 works to some extent without n-serve is that there is an immediate flash kill of about a 6"circular band of soil bacteria including nitrifying bacteria that are needed to convert the nh3 to nitrate before it can leach through the soil structure. When fall urea is applied without n-serve, there is no flash kill and no chemical resistance therefore it becomes extremely susceptible to conversion and leaching. When n-serve is added to the equation the scenario changes entirely. N-serve is a bacteria killer. The more concentrated the n-serve band, the longer it will hold back the nitrifying bacteria. A tight 1" band of urea treated with n-serve is therefore much more stable than a 6" circular band of nh3. Therefore the same attribute of a 6" circular band that benefits the nh3 without n-serve becomes a detriment with n-serve. With urea you are only "holding back" the nitrifying bacteria from a 1" band of fertilizer. With nh3 you are killing a 6" plume of all bacteria and diluting your n-serve. Its like the difference between a shotgun and a riffle. The shotgun will give you a broader target, but the riffle is more targeted and deadly. With n-serve, we need to be targeted to protect the bacteria in our soil. The more years you spend away from nh3, the healthier your soil will become. Visit us at www.lynxag.com