Loblolly Genetics: Performance & Value in a 20-Year-Old Plantation

Advanced Genetics Delivers Added Value to Forest Landowners

Southern pine landowners now have it all. In the past, forest products corporations had the best genetics, the best genetic data and financial analyses to grow high productivity tree plantations. Now, however, private landowners and consultants have access to all three. This article will share the long-term results of an MCP^® hybrid field trial that demonstrates the substantial value increase over Open Pollinated seedlings. ArborGen is the only seedling producer with such long-term data and publishing it reflects our goal of transparency as a reforestation partner with our customers.

Since 2009 the amount of control pollinated hybrid loblolly pine genetics has steadily increased in the U.S. seedling market and has grown almost 25% per year since 2016 (Figure 1.). ArborGen’s MCP seedlings represent 80% of the open market sales of these hybrids.

Figure 1. Annual production of full-sibling crosses of loblolly pine seedlings (Unpublished data from NCSU-CTIP).

Observing and verifying financial value produced in a forest plantation takes a long time, but there are few documented examples that demonstrate how the genetics of seedlings has impacted stand value over a rotation. A long-term field trial initially established by MeadWestvaco in the South Carolina Lowcountry in 1998 compared a widely planted open-pollinated family, 7-56, to ArborGen’s MCP family AGM-22. ArborGen previously published the growth data at 12 years that showed the value of planting elite loblolly MCP pine hybrids. The 20-year results were even more impressive and confirmed the projected growth from the 12 year study.

A look at age 20 results

With a trend that began at age 4 (Figure 2), MCP family AGM-22 had the most significant growth rate in the trial and a significantly higher proportion of sawtimber quality trees both before and after thinning. AGM-22 is exhibiting a growth rate of 8.3 green tons/acre/year compared to 7-56 that is growing at 6.7 tons/acre/year. The combination of superior growth rate and high-quality logs is the basis of the significantly higher financial returns that are possible with MCP families such as AGM-22 demonstrated with this trial. The data also show that early data, as seen in Figure 2, is predictive of long-term results.

At age 12, we also observed that 7-56 was left with only 48 ft2/ac of basal area compared to 70 ft2/ac in AGM-22. This means the 7-56 stand was severely understocked after removing all the defective trees in the thinning.

At age 20, eight years after thinning, AGM-22 has maintained a 7-foot height advantage and a 19% tons per tree advantage compared to 7-56. Combining the per tree growth gains with the higher number of sawtimber logs after thinning, AGM-22 has 46% more tons of wood (116 tons) per acre compared to 7-56 (80 tons) and virtually all of these are sawtimber tons.

Figure 2. Volume per tree for AGM 22 (CP-1) vs. 7-56 (OP-1) from Age 4 to 20 years.
In Table 1, The MCP family, AGM-22, demonstrates the value of advanced genetics that comes from genetic testing and development with a 61 percent increase in Net Present Value (NPV) and a 60 percent increase in Revenue at final harvest over the OP family, 7-56.

Table 1. Summary of Product Yields* (tons/ac) and Financial Metrics ($/ac, %) for a projected harvest at age 25.

Landowners now have access to the best genetics, field trial data, and financial performance information to allow them to be confident in their seedling genetic investment. Advanced genetic products such as control-pollinated seedlings (MCP) offer additional value over traditional OP seedlings even using today’s log prices. This 20-year-old trial in the lower coastal plain of South Carolina provides insight into the performance of this hybrid, control pollinated genetics demonstrating the growth and financial gains that are possible in loblolly pine plantations
The exciting news is that these elite hybrid seedlings with these same pedigrees are available today for private landowners and consultants across the southeastern United States.

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