A provisional growth model with a size–density relationship for a plantation of Paraserianthes falcataria derived from measurements taken over 2 years in Pare, Indonesia

Abstract

A growth model for a plantation of Paraserianthes falcataria was provisionally derived from measurements of 32 permanent plots taken over a period of 2 years in Pare, Indonesia. This model first predicts height growth with the polymorphic site index equation. Then density-related growth and mortality, that is, diameter and stand density, are calculated to satisfy the mathematical relationship for the reciprocal and self-thinning equations, both of which were based on the maximum size–density line with the slope of –1.759 identified in this study. Cumulative predictions on diameter and stand density, starting with each of three age classes, 3, 4, and 5 years after planting, and continuing for the next 2 years, agreed well with the observations of age-class mean. An exception was for stands that were 7 years old, which were marginal, but closest to the rotation age of 8 years. Contrasting height/diameter relationships among the three age classes were described reasonably well with this model, and the predicted basal growth area was found to agree fairly well with observations. These results suggest that the growth model presented here has good potential for applying size–density control for plantations of P. falcataria. However, measurements for an additional few years might be necessary to derive a model that will more accurately predict diameter size at the rotation age.

Keywords:

• Maximum size–density line
• Paraserianthes falcataria
• Reciprocal equation
• Self-thinning
• Site index curve

Acknowledgments

The authors would like to thank Mr. Sadhardjo, the former director of the Teak Center, and Ms. Ela and Mr. Umar, research staff of the center at Perum Perhutani, for their support in collecting data from permanent plots of P. falcataria in Pare, Indonesia. We are also grateful to Dr. Miyaura, a professor at Ryukoku University, for his advice on the earlier version of the paper, and the research staff of Mr. Kato at the Sumitomo Forestry Company Ltd. for their support with literature on P. falcataria. This research was supported by the Global Environment Research Fund B-S21b from the Ministry of Environment of Japan.