Although animal manures can be a rich source of nutrients for crops, the nutrients found in them–whether from swine, beef cattle, dairy cows or poultry–are not always in a form that is readily available for crop uptake.
Phosphorus is a good example. With its negative charge, phosphorus easily binds to positively charged micronutrients, such as those found in animal rations or dairy cow footbath solutions. Once bound, it remains in a form that is unavailable to the plant until transformed through natural processes (e.g., weather, soil microbes) or agronomic management. As a result, growers who have been applying animal manures may see high levels of unavailable phosphorus on their soil tests (indicated by a high Bray P2 value), but a deficit of plant-available phosphorus (low/lagging Bray P1).
Extract PBA, which helps to convert P2 to P1, is one of the agronomic tools available to help growers be more efficient with their nutrient applications by making phosphorus and other nutrients found in manures, crops residues and the soil more readily available for crop uptake.