Volume Gains of Rooted Loblolly Pine Clones at Age 10 in Florida and Alabama

An estimate of the growth potential of clonal lines produced from elite crosses compared to trees grown from seed is needed to justify clonal forestry programs. A series of age 10 loblolly pine (Pinus taeda L.) rooted cutting tests planted in Nassau County, Florida and Monroe County, Alabama are some of the oldest clonally replicated studies in existence. A 3 X 3 factorial produced 9 cross families from which 4-6 clones were produced as rooted cuttings from seedling hedges. Clones and seedlings were planted in a randomized complete block design with split-plots for seedlings and rooted cuttings. Clone genetic values were estimated by Best Linear Unbiased Prediction method and genetic gains were estimated for various clone selection scenarios. Average volume gain over the family mean estimate by choosing the best clones from each family was 12.6%. The top clone of the 45 tested clones yielded 39.8% more volume than the grand mean. The top five and the top 10 clones had 30% and 23% more volume gain than the grand mean, respectively.Papers and abstracts from the 27th Southern Forest Tree Improvement Conference held at Oklahoma State University in Stillwater, Oklahoma on June 24-27, 2003