Reply #5: not into thin air [View All]

[Tashca]

My education comes from land grant Universities and the fertilizer industry. So take what I have to say with a grain of salt....I try and sort it out the best I can.

Nitrogen and Sulfur are very mobile in the soil...they follow the water table closely. They are also very soluble when they are in the form the plant can use. That is why Nitrogen in particular ends up in our surface water....and in some cases our ground water.

Potassium and Phosphorus are relatively immobile. The ways they are removed from the soil are through crop removal and soil erosion. Both bind to the soil fairly well. The problem with them in the way they are currently used....when they breakdown and are available for use to the plant it is a relatively short time. They are very susceptible to chemical tie up with other soil particles. To get enough available to raise the high yields that are currently being produced.....the stuff is over applied to make sure there will be a source when needed. Most of what is understood about the process is chemical....we are just starting to learn about the biological processes. In my opinion we have sufficient fertility for many years out in most of these fields....but it is chemically tied up.....unavailable.. We need to learn how to untie them for plant use. I think the secret is through biological processes...

I am familiar with the Thompson's....and I agree that we can learn from their system.