Fertilizers are applied to over a million acres of forestland annually. Some trees, particularly slash and loblolly pines, can respond dramatically to proper fertilization. Response is best when other intensive management practices are being applied and on nutrient deficient sites. Knowledge of your soil type and soil conditions, combined with a soil test to determine the siteís soil fertility status, will help identify sites and stands that will respond to specific fertilizers.


Proper Soil Sampling and Analysis for Nutrient Needs Determination in Loblolly, Longleaf, and Slash Pine Stands
Most land-grant universities have Agricultural Service Laboratories that perform testing for soil and foliar nutrients. Call your county Extension office to see if they provide soil and foliage testing services. If so, get several soil boxes or bags from the nearest office. Some private labs can also perform these analyses. Both soil and foliage tests can indicate if a nutrient is below a "critical level", "sufficiency level", or "minimum guideline" which assumes that a stand will respond to fertilization of that nutrient.


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
Between 500,000 to 1,200,000 pine plantation acres (primarily loblolly) have been fertilized annually since the mid-1990's in the southeastern U.S. Common pine stand fertilization "windows" are at pine stand establishment (pre-plant or within two to three years of planting to rectify a phosphorus (P) or nitrogen and phosphorus (NP) deficiency) and at mid-rotation (after canopy closure to enhance pine straw production and tree growth or after a thinning using NP or NP+postassium (K)).


A checklist for fertilization of loblolly, longleaf and slash pine stands
Economically beneficial southern pine stand fertilization depends on three primary factors: (1) the expected wood yield and pine straw increases from the application of the fertilizer materials, (2) their market values at time of harvest, and (3) the fertilizer material and application costs. The resulting revenues from the extra wood and pine straw grown with fertilization must exceed the cost of fertilization.


Phosphorus Fertilization at Establishment in Loblolly and Slash Pine Stands on Atlantic and Gulf Coastal Plain Sites
Forest fertilization in the south has increased greatly since the 1960s. In 2000 and 2001 over 1.2 million acres per year of southern pine plantations were fertilized (NCSUFNC 2002). The predominant species fertilized are loblolly (Pinus taeda L.) and slash (Pinus elliottii Engelm. var. elliottii) pine. Fertilization can enhance loblolly and slash pine growth and financial returns.



Opportunities for Fertilizing Pine Plantations
Fertilizing pine plantations has captured the attention of forest landowners across the South. While the majority of stands receiving fertilizer treatments are on forest industry lands, private nonindustrial landowners are increasingly willing to consider fertilization. Growth benefits can be gained from fertilizer applications, but a good prescription is needed to insure economic response as growth responses can vary greatly across soil and drainage classes. Before you begin any fertilization program consider several points.

Fertilize to optimize your forestís timber production potential
From the August 2004 issue of The Forestry Source - Dr. Micheal Blazier


Straw Raking in Southern Pine Stands and Fertilization Recommendations
Pine straw, the uppermost forest floor layer of undecayed needles, is raked, baled, and sold as landscaping mulch in the southeastern U.S. The value of pine straw as a forest product is increasing in Georgia. Forest landowners in Georgia received $15.5, $17.5, and $22.4 million revenues from pine straw in 2000, 2001, and 2002, respectively (Boatright and McKissick 2003). Conversely, annual timber revenues in Georgia have declined by over 18% during this same period (Boatright and McKissick 2003). Pine straw revenues have helped many landowners maintain reasonable cash flows to achieve attractive rates of return (Dickens et al. 2001) on their forestland. Internal rates of return can be increased from 8 to 11 % without pine straw production to 13 to 20 % with annual pine straw income in loblolly and slash pine stands (Dickens et al. 2001).


Pine Plantation Fertilization
Forest fertilization has increased greatly since the 1960s. Currently, there are an estimated 33.7 million (M) acres of loblolly pine, 10.4 M acres of slash pine, and 3 M acres of longleaf pine stands in the Southeastern U.S. (2001 figure). Approximately 1.3 M acres of loblolly and slash pine stands are fertilized in this region.
Fertilization can increase loblolly, longleaf, and slash pine wood volume, pine straw production (used for
mulch in landscaping), and per acre revenues. Fertilizer recommendations should be site-specifc and be based on soil type, land use history, control of competing vegetation, pine species, age, stocking (trees/A), and target products (pulpwood, sawtimber, poles, pine straw) to maximize fertilizer benefit.