Volume growth of pine and hardwood in uneven-aged loblolly pine-upland hardwood mixtures
Results are reported from an exploratory investigation of stand-level periodic volume growth of uneven-aged mixed loblolly pine (Pinus taeda L.)-upland hardwood stands on good sites in southeastern Arkansas. A restricted set of replicated observations was extracted from an extensive CFI database involving varying pine-hardwood mixtures to form an array of plots with different levels of pines and hardwoods. Analysis was conducted of the 5-year periodic annual increment of the pine, the hardwood, and the total (pine plus hardwood) in relation to the stand density of the pine and hardwood components. Results show that at low to moderate pine basal area levels, an added hardwood component increases total stand growth but decreases total growth at higher pine levels. There seems to be little or no economic justification for mixed stands based on these growth predictions and current stumpage prices. The implications of these results and other factors regarding mixed stand management are also discussed.