Role of Soil Properties In Influencing Clonal Loblolly Pine (Pinus taeda) Growth In the Virginia Piedmont.

Loblolly pine (Pinus taeda) is the dominant plantation species in the Southern United States.  With a global increase in population and an associated demand for forest products, foresters are seeking ways to increase productivity at the same time that productive forestland are being degraded or lost to urbanization.  With the recent advent of clonal pine forestry, scientists are trying to determine what increases can be expected from plantation-scale plantings of highly productive genotypes.  While genetic variability has been eliminated on single-clone plantations, the importance of the genetic/environment interactions (GxE) becomes increasingly important.  Understanding the role of soil properties in influencing tree growth is essential to understand these GxE interactions while controlling for the genetic variability.  At the northern edge of loblolly range on the Virginia piedmont, sixty individual 3-year old loblolly pines of a single genetic strain were randomly selected and intensively measured over the 2010 growing season for growth characteristics and soil properties.  From a 1m radius around each individual, repeated measurements of soil strength, moisture, temperature, and one time measurements of slope, texture, bulk density, and landscape position were taken.  Due to soil heterogeneity across the landscape, tree growth in every metric varied immensely.  This study will determine which soil properties, in the absence of genetic differences, are responsible for differences in tree growth.