Comparison of advanced genetic loblolly pine planting stock
This article is part of a larger document. View the larger document here.Abstract
Forest landowners have several options when it comes to selecting planting stock for loblolly pine plantations. The majority of plantations established over the past two decades have been planted with 2nd-Generation open-pollinated (2nd-Gen) seedling stock. Today, landowners can increase their yields using more sophisticated planting stock such as Mass Control Pollinated (MCP) or Varietal (clonal) stock. Substantial gains have been estimated when using either MCP or Varietal stock. Forest biotechnology firms are currently producing loblolly pine varietal planting stock for deployment in the southeastern US. Currently, however, the cost of varietal planting stock is considerably higher than that of both standard open-pollinated and MCP seedlings. Landowners need to know if the increased gains from the improved genetic material will be great enough to offset increased plantation establishment costs. In 2007, a Loblolly Pine Genetic Level Study was installed in northern Mississippi to examine differences in growth and form among 2nd-Gen, MCP, and Varietal planting stock. Third-year measurements showed that on average, MCP trees were significantly taller than either the Varietal or 2nd-Gen stock types. However, the top five performing varieties averaged nearly 0.5 feet taller than the MCP trees, and 1.0 feet taller than the 2nd-Gen stock. Results from fourth-year measurements will be presented.