Successful fertilization of a pine plantation depends on many factors; the soil test level is one of those. Soil testing begins with proper sampling of soil from the area to be planted. Soil sampling procedures are described in the publication "Proper Soil Sampling and Analysis for Nutrient Needs Determination in Loblolly, Longleaf, and Slash Pine Stands", which is located at http://www.forestproductivity.net/fertilization/ or http://aesl.ces.uga.edu/publications/soilcirc/.
Profitable fertilization of pine stands depends on many factors that are outlined in the publication "A checklist for fertilization of loblolly, longleaf and slash pine stands".
This publication is located at http://www.forestproductivity.net/fertilization/ or http://aesl.ces.uga.edu/publications/soilcirc/.
In making decisions about fertilization, numerous stand factors described in this publication should be considered.
In addition, soil series and land use history should be combined with the results from the three diagnostic tools listed: 1. Soil testing, 2. Foliage testing, and 3.Leaf Area Index.
Finally, the economics in making fertilizer rate decisions should be considered as described in the publication "Mid-rotation rate of return (ROR) estimates with a single nitrogen + phosphorus or nitrogen + phosphorus + potassium fertilizer application in loblolly, longleaf, and slash pine stands".
This publication is also available at the two websites given above.
A calculator at http://aesl.ces.uga.edu/soil/pine can help you determine the rate of return if you provide rates of N, P, and K fertilizer, their cost, the expected extra growth from fertilization, and the value of the extra wood produced.