Loblolly pine - Pushing the limits of growth

Abstract

With mean annual increments up to 5.4 cords/ac/yr, six loblolly pine (Pinus taeda L.) research sites in Georgia produced yields on par with other results from intensively managed loblolly plantations around the world. Cultural treatments in the Georgia study include complete control of vegetation other than the planted pines with multiple applications of herbicide, annual fertilization, the combination of complete vegetation control and annual fertilization, and an intensive mechanical site preparation treatment. Complete vegetation control resulted in higher yield production at ages 10 to 12 yr than the intensive mechanical treatment at all locations. This regime also resulted in higher yield production than the annual fertilization treatment at four of six locations. Volume mean annual increment for 10- to 12-yr-old plantations with the combination treatment of complete vegetation control and annual fertilization ranged from 325 to 490 ft3/ac, growth rates comparable to those obtained at other high biomass production areas throughout the world. Our economic evaluation based on these results shows that 8 to 12% real rates of return are feasible from investments in intensive loblolly pine plantations in the southeastern United States. South. J. Appl. For.