|
Little River, TX | From what you say I gather your soil is not a high pH, nor have a high natural calcium level. I have no understanding at all of acid soils, but I am told in acid soils aluminum will tie up phosphate just as calcium does on my soils. In that case Avail possibly will help.
Here I have an 8 pH, excessively high calcium levels (6,000 ppm Ca), and adding to my problems 10% Free Lime. For me to change my phosphate soil test values requires 70 lbs/A of P2O5. I can help the situation a little by banding on the surface or better yet deep banding using chisels. One option that helps is to put phosphate down the same chisel slot as we put anhydrous. The ammonia helps slow the conversion of P2O5 to one of many different calcium phosphate molecules. In this case, supposedly, Avail will temporarily react with calcium, magnesium, sodium, ammonium, and a number of heavy metals and allow the phosphate to remain in an reasonably available form for longer than a few days. The reason I mention free lime in the soil is there is a theory. Supposedly in a neutral soil 16.6 lbs of P2O5 will change the soil test by 1 ppm. Now for each percentage of free lime an additional 10 lbs of P2O5 is required to have the same crop response.
Here in Central Texas, on our tight black clay soil with an abundance of calcium, can be a real interesting challenge. A number of years ago someone made the educated guess my soil contains 145 tons of Ag Lime per acre in the top 6 feet of soil. | |
|