Details for Removing Excess Soil Phosphorus Levels: A Practical Approach

High P is an asset BUT you need to manage other nutrients such as zinc and magnesium to draw down the phosphorus levels over time. Growing forages and taking them off the field will draw levels down. It would be interesting to know more information, such as the pH of your soil, and the extraction level that you are using to provide the phosphorus readings 

Having high Phos levels can be both a blessing and a curse. A blessing because it's there but a curse because it's hard to access. What are your P levels? Whats the pH of your soil? What soil type do you have? Using up some of this P is a great plan but what nutrients might you be lacking in that could be your limiting factor? Fortunately there are lots of tools at your disposal these days. There are lots of great products with great claims but you never know exactly what works for you unless you try it. Cover crop and humic acids can help feed fungi which can help make P more available. There is patented bacteria, bacillus firma which solubilizes P in soil, you can also work on key ratios in the soil to help balance nutrients and enhance P availability.

Potential option would be Humics, we have a sales rep in your area who would be happy to dive more into this if your interested. My gut would say you are wanting to activate your phosphorus in your soil so you can apply less at seeding or in-season, is that correct? Www.blackearth.com we have an article specifically talking about the relationship between humics and phosphorus!

Zn and Fe deficiencies CAN be a symptom of excess soil P2O5 levels (in production ag)

This is copied from a popular garden-plant manual: Unfortunately, there are no ways to actively reduce excessive phosphorus in garden soil. In working to moderate phosphorus levels in the garden, it will be imperative that growers avoid the use of fertilizers that contain phosphorus. Avoiding the addition of phosphorus for several growing seasons will help reduce the amount present in the soil. Read more at Gardening Know How: Lowering Phosphorus I have encountered very high soil P2O5 levels due to long term over fertilization with NPK commercial fertilizers. With soil testing widely available, over-fertilization SHOULD be a thing of the past, but some specific regions are dealing with past issues. Excessive phosphate soil levels usually are expressed by severe Zinc and/or Iron uptake by plants, regardless of soil test levels of these elements. Timely foliar applications may be a benefit in some cases. As the previous commenter suggested, be sure you KNOW precisely what your soil phosphorous levels are and the testing method used by your laboratory are appropriate for your soils (there are several different analytical procedures for specific soil types & characteristics; Bray 1, Bray 2, Olson test, Melich 3, etc.). Use advice from a professional soil testing lab and/or local crop advisor to determine your best test and interpretive values. Avoid over fertilization for the obvious expense management as well as environmental degradation.

Keep levels of all other macros and micros adequate to high especially Sulfur and remove it from the field as high yield grain is about all you can do.

1st question, What do you call high? 2nd why do you want to bring them down, I’m not saying you’re wrong, most other people are trying to build theirs, high phos levels can bring challenges, typically we recommend ways to manage around it