In total 60 plots of approximately 80 trees each (including missing trees) were measured, with ages between 1 and 26 years. The main objective of this study was to develop intensive management scenarios for B. quinata plantations in Costa Rica to ensure high yielding of timber wood. The scenarios were based on a fitted curve for the relationship of DBH, and total height with age. A criterion of maximum basal area (18, 20, 22 and 24 m2 ha-1) was used to simulate different site qualities. Plantation density was modeled as a function of the crown area occupation of the standing trees. The scenarios consist of rotation periods between 23 and 30 years, final densities of 100-120 trees ha-1, mean DBH between 46 and 56 cm, and mean total heights of 30-35 m. The productivity at the end of the rotation varies between 9.6 and 11.3 m3 ha-1 per year, yielding a total volume at the end of the rotation of 220-340 m3 ha-1. The scenarios presented here may provide farmers and private companies with useful and realistic growth projections for B. quinata plantations in Costa Rica.
Tag: rotations
Acacia mangium plantations in PT Musi Hutan Persada, South Sumatera, Indonesia
PT Musi Hutan Persada, a forestry company growing wood for pulp in South Sumatra manages about 200 000 ha of forest plantations, 90% of which consists of Acacia mangium. Most of the plantations are in an area with high rainfall and on red-yellow podzolic soil with inherently poor fertility and low pH. Inter-rotation site productivity and management have been identified by the company as one of the crucial issues for sustaining the long-term productivity of its plantations. This paper describes the study plan for inter-rotation site productivity and management of A. mangium plantations in PT Musi Hutan Persada. The experiment tests the on-site effect of different treatments of organic matter or aboveground biomass management. Information from earlier work indicates that most A. mangium biomass and three major nutrients (N, P and K) is in the wood, and harvesting will remove around 200 kg N, 45 kg P and 240 kg K per hectare. Litter production of an 8-year old stand was about 13 t ha -1 and about 70% of its mass will be lost in one year.