PREDICTED LEAF-AREA GROWTH AND FOLIAGE EFFICIENCY OF LOBLOLLY-PINE PLANTATIONS

Foliage dynamics research is helpful for better understanding the proc ess of forest production and improving silvicultural practice. However , the difficulty of measuring foliage amount has slowed down the resea rch progress. Since leaf area of an individual tree can be reliably pr edicted from its diameter, growth and yield models that provide detail ed information for each diameter class can be used to benefit foliage dynamics research. Simulation results from a growth and yield system f or unthinned loblolly pine plantations indicated that foliage area inc reased with stand age, peaked between ages 36 and 51, and decreased af ter that. Volume growth increased with leaf area for young stands and decreased for older stands, whereas foliage efficiency consistently de creased with age. Better sites supported higher levels of leaf area in dex, volume growth, and foliage efficiency. Higher planting densities led to higher maximum leaf area indices and shorter time to reach that level. Initial density had no effect on foliage efficiency through ti me. (C) 1997 Elsevier Science B.V.