Breeding & Testing Today to Produce

More Profitable Trees Tomorrow

Each year ArborGen’s Geneticists select families to breed and test to maintain our position as the company with the best pine genetics on the market. Each time we add a family to the ArborGen portfolio, we increase the overall quality and benefits to the landowner, including added volume, reduced fusiform infection, straighter trees and/or trees with fewer forks. Increased volume and improved quality mean increased revenue for higher-priced products such as chip-n-saw, sawlogs, plylogs and poles.

ArborGen participates in all three University Tree Improvement Cooperatives at N.C. State University, the University of Florida and Texas A&M University. However, ArborGen also conducts proprietary breeding and testing using traditional and genomics technology to bring the most genetically advanced seedlings to our customers.

One of the major objectives of breeding and testing for ArborGen is to identify new parent trees for the production of Mass Control Pollination (MCP®) seedlings. Specific crosses are carefully selected and, in the spring, flowers are bagged and specific pollen from another selected tree is blown into the bag. After cones are harvested and seed extracted and labeled, these seeds are sown in April and grown at our Ridgeville headquarters until the fall.

The Product Development group selects sites each year for progeny tests that consist of good soils with low variability. We focus on sites that represent the soil groups and physiographic regions most commonly planted with pines by our customers. Tremendous importance is placed on selecting planting sites where we can separate the genetic variation among families being tested from the environmental effects of the site. ArborGen currently has over 750 field trials of loblolly and slash pine across the southeastern United States.

Once the site is selected, proper chemical site preparation is conducted, and the site might be subsoiled to break-up any hardpan or soil compaction that may have developed over time from machinery. On wet sites, we also bed the site to further reduce variability of the site and provide optimal conditions for survival and growth.

Finally, the site is marked-off with pin flags, designating where each seedling will be planted. Many of the test sites are established with single tree plot designs where we plant 50 or more untested families. Each family will have 10 to 20 seedlings randomly planted across the test to help minimize bias in the performance of the trees.

Additionally, we include some families in the test that have been tested in previous years, allowing us to compare and rank the new families against the known families already in our reforestation portfolio. Once the test site has been planted, ArborGen’s Research Associates manage the site to be free of competition, including weeds, grasses, hardwood and pine trees that sprout and grow on site.

The trees are measured at least twice at ages three and six years. The data collected for each tree is height and diameter for volume estimates, presence or absence of fusiform rust, straightness and forking. Additionally, we measure stem sweep and take wood cores for specific gravity. The age six progeny test data from all test sites are entered into a database and compared to each other. They are also compared to known families in the database and ranked by the four major traits listed above. The newly tested progeny that rank high in those traits are added to the portfolio of families to sell.

Article by: Donnie Fleming – Pine Product & Sales Support, and Patrick Cumbie, Ph.D. – Manager, Pine Development

Planting Tips

Maximize your seedling survival by avoiding these common planting mistakes.

“J” or “U” Roots
Roots form “J” or “U” shape resulting in poor or weak root development.

Seedling Availability

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