This paper provides a global overview of forest plantation growth rates, with a particular focus on mean annual volume increment (MAI) of the main species planted in developing countries. Documented growth data from both trials and plantations is presented, and the difficulty of translating trial data to commercial scale is highlighted. The main technical issues and pitfalls relating to MAI measurement and the preparation and growth models used are included. This paper concentrates primarily on presenting data for the most important industrial species. A brief description of major efforts to improve data on plantation growth performance and make it more accessible is described.
Currently, eucalypts and pines are the most commonly used species in tropical timber plantations; together, they account for 43 percent of all tropical plantation area. Pines dominate temperate and boreal plantations; 54 percent by area. Productivity of tropical plantation forests grown on short to medium-term rotation lengths varies greatly from 1-2 m³ ha-1 yr-1 to 25-30 m³ ha-1 yr-1.
The large variability found on productivity is due mainly to species behaviour, site quality, genetic material, plantation age and silvicultural management. Growth increment and quality yields vary considerably even between varieties, as is the case of P. caribaea.
Eucalypts are recognized as the some of the fastest growing trees and some of them are preferred because of its high growth rate, short rotation length (10 years) and favourable pulpwood properties.
For the most fast growing species growth rates are highest with favourable temperatures and where there is high soil water-storage capacity and good fertility. However, sustaining tree productivity in the future will depend on maintaining soil fertility levels in subsequent plantation rotations.
