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Abstract
The hardwood component of young loblolly pine (
Pinus taeda L.) plantations was simulated for use in a sampling study of competing vegetation. Spatial arrangement, total height, and crown area of hardwood rootstocks in 19 plantations 3 to 6 years old in Alabama and Georgia were used to develop the simulator. Rootstock arrangement ranged from uniform to clumped. A two parameter, left- and right-truncated Weibull function modelled height distribution. Total rootstock height conditionally determined crown area. The simulator was used to evaluate 42 sampling estimators of competing hardwood vegetation. Bias, precision, and variance of the estimators were compared. All estimators were relatively unbiased at low sampling intensities. Rootstock clumping reduced precision and increased variance. Variable plot estimators exhibited greater precision and lower variance. Horizontal variable plot estimators are recommended for use in quantifying the amount of competing hardwood vegetation in young loblolly pine plantations.
Citation
Weise, D.R.; Glover, G.R. 1990. Simulating and sampling the hardwood component of loblolly pine plantations. In: Wensel, L.C.; Biging, G.S., tech. eds. Forest simulation systems: proceedings of the IUFRO Conference. Oakland, CA: University of California, Division of Agriculture and Natural Resources: 199-206.