Assessment of plantation productivity in first and second rotations of Pinus radiata in New South Wales

Summary Productivity of the first and second rotations of Pinus radiata (D. Don) plantations was evaluated at seven sites on four parent rock types in New South Wales. The comparisons were made at ages 11, 14, 18, 19, 20 and 24 years using data from first rotation (RI) and second rotation (R2) stands collected from (1) adjacent compartments, (2) the same compartment and (3) the same plots. The results show no overall decline in the productivity of R2 stands, although there were some fluctuations. Mean dominant height, diameter at breast height, basal area and stand volume of R2 stands were generally greater than those of R1 stands. The mean increases in stand basal area and volume were about 13% and 18% respectively. The most significant increase in productivity was found in young stands but the advantage declined after age 20. The superior productivity of R2 stands was generally attributed to better site preparation, seed sources, weed control and fertiliser applications.