Deep
phosphorous incorporation is a new technique developed by the Soil Science
Department at North Carolina State University. Using this method, a single
band of fertilizer is placed 12 inches deep directly below the row using a
modified sub-soiler (click here to see pictures).
Best results and the least chance of tree injury are obtained using 0-46-0
(triple super phosphate) fertilizer at a rate of 200 to 400 pounds of phosphorus
per acre. This is far less phosphorus than would be needed if fertilizer was
only applied to the surface after transplanting.
Deep incorporation causes minimal surface disturbance, as shown by the picture on the right. In contrast, conventional incorporation by disking or plowing leaves the soil surface bare and greatly increases the danger of soil erosion and phosphorus loss.
