Ok - so I don't put people on blast, that isn't my goal but I have to share.
I have seen a lot of "trophy photos" of food plots recently and what follows is a blind fertilizer recommendation, for example - put down X amount of N per acre and you to can grow this crop! Also, typically some seed blend is then promoted thereafter.
Please do not do this - before taking on a fertilizer recommendation, we must get a soil sample. Even a conventional soil sample doesn't account for all the organic N in the soil - this is why guys like Dr. Rick Haney, John Kempf, etc. are finding that most often we are over-applying N - this is just a waste of money, not to mention other ecological potential harms. This is also why farmers stagger N applications, starter, foliar, band some on, etc. They don't just DUMP N on the ground and hope for the best.
Most conventional tests only account for Nitrate N in the soil. Nitrate N is also the most likely to leach, and least stable N source. Urea, for example, is in amid form- which is quickly converted to nitrate by soil microbes. This is why UREA is often mentioned as evaporating quickly. If we can work UREA into the soil, we are more likely to have it converted to ammonium - which is a far more stable N source - compared to nitrates. Most of the time we are not able to work it into the soil, as it is being top-dressed after planting.
So what happens to that extra N?
Well, it leaches out - and can add to the pollution of our rivers that many housing developments and other reasons are already exacerbating by over-fertilization.
Some of it will just evaporate - which is a total waste of money.
An overabundance of N can also drive CA (calcium) of the soil colloid, driving up the MG levels in the soil - which can lead to compaction, poorer aggregation, etc.
An overabundance of N can also make our plants lazy. We want our plants to exude acids/sugars/carbon into the soil profile to communicate with our microbiology, and take advantage of the organic forms of N (amino acid proteins) - not solely being reliant on being force-fed.
There is also the threat of REDOX reactions (oxidation) occurring when we over-apply salt-based fertilizers which will cause oxidation to occur- this reduces microbial activity and binds up needed nutrients like iron, making them insoluble.
All this to say, when in doubt - get a soil test. If you are really interested in what is missing, pull some leaf samples and send those in for plant tissue/sap eval.
Interesting link explaining the nitrogen cycle:
There are three main causes of potential nitrogen loss: volatilization, denitrification and leaching. Explore how to maximize usable nitrogen in your fields
taurus.ag
Food for thought.
AT