Mean annual volume increment of selected …

1 Forestry DepartmentFood and Agriculture Organization of the United NationsForest Plantations Thematic PapersMEAN annual volume increment OF selected INDUSTRIALFOREST PLANTATION SPECIESB ased on the work ofLuis Ugalde and Osvaldo P rezConsultantsEdited by D. J. MeadApril 2001 Forest Resources Development Service Working Paper FP/1 Forest Resources DivisionFAO, Rome (Italy)Forestry Department2 DisclaimerThe Forest Plantation Thematic Papers report on issues and activities in forest plantations as prepared for FRA2000. These working papers do not reflect any official position of FAO. Please refer to the FAO website( ) for official purpose of these papers is to provide early information on on-going activities and programmes, and tostimulate and feedback are further information please contact:Mr.

2 Jim Carle, Senior Forestry Officer (Plantations and Protection),Forest Resources Development ServiceForest Resources DivisionForestry DepartmentFAOV iale delle Terme di CaracallaI-00100 Rome (Italy)e-mail: quotation:FAO (2001). Mean annual volume increment of selected industrial forest plantation species by L Ugalde & OP rez. Forest Plantation Thematic Papers, Working Paper 1. Forest Resources Development Service, ForestResources Division. FAO, Rome (unpublished).3 ABSTRACTThis paper provides a global overview of forest plantation growth rates, with a particularfocus on mean annual volume increment (MAI) of the main species planted in developingcountries.

3 Documented growth data from both trials and plantations is presented, and thedifficulty of translating trial data to commercial scale is highlighted. The main technicalissues and pitfalls relating to MAI measurement and the preparation and growth models usedare included. This paper concentrates primarily on presenting data for the most importantindustrial species. A brief description of major efforts to improve data on plantation growthperformance and make it more accessible is , eucalypts and pines are the most commonly used species in tropical timberplantations; together, they account for 43 percent of all tropical plantation area.

4 Pinesdominate temperate and boreal plantations; 54 percent by area. Productivity of tropicalplantation forests grown on short to medium-term rotation lengths varies greatly from 1-2 m ha- yr- to 25-30 m ha- yr- .The large variability found on productivity is due mainly to species behaviour, site quality,genetic material, plantation age and silvicultural management. Growth increment and qualityyields vary considerably even between varieties, as is the case of P. are recognized as the some of the fastest growing trees and some of them arepreferred because of its high growth rate, short rotation length (10 years) and favourablepulpwood the most fast growing species growth rates are highest with favourable temperatures andwhere there is high soil water-storage capacity and good fertility.

5 However, sustaining treeproductivity in the future will depend on maintaining soil fertility levels in subsequentplantation Eucalyptus Eucalyptus Eucalyptus Eucalyptus Eucalyptus Eucalyptus Eucalyptus Pinus caribaea var. Pinus caribaea var. Pinus Pinus Pinus Acacia mearnsii and A. Araucaria angustifolia and A. Casuarina Cordia Cupressus Dalbergia Gmelina Leucaena Switenia Tectona Terminalia ivorensis and T. superba175. Difficulties Translating Trial Data to the Field176. Growth Models187. Improving accessibility to plantation growth data19 References20 Appendix plantations, which are expanding rapidly in the tropics and sub-tropics will clearly playa very important role in the future world wood supply (see Working Paper FP/ paper 13).

6 Currently, eucalypts and pines are the most commonly used species in tropical timberplantations (Evans 1992); together, they account for 43 percent of all tropical plantation area(FAO 1999). Pines dominate temperate and boreal plantations; 54 percent by area (FAO1999).Productivity of tropical plantation forests grown on short to medium-term rotation lengthsvaries greatly from 1-2 m ha- yr- to 25-30 m ha- yr- (Table 1 and Appendix 1). A similarrange is found in temperate countries (Evans 1992, FAO 2000). Higher yields have beenreported for some species and situations.

7 However, while the potential for achieving highproductivity is clearly evident, there are many constraints on yield (see Working Papers FP/3and 15) and perhaps sustainability (see Working Paper FP/2) or environmental 1. Productivity and rotation lengths for main forest plantation trees in selected tropicalcountriesSpeciesRegionCountryRot ation length(yr)MAI(m ha- yr- )EucalyptsS. America Africa8-1018-20 PinesS. America : Brown et al paper focuses on the main tropical and subtropical forest plantation species. The keymeasurements discussed are mean annual increment and rotation length.

8 Mean annualincrement (MAI) is defined here as the merchantable stand volume at harvesting divided bythe stand age (rotation length), although in some instances MAI for pre-harvesting stands arealso discussed. Unless otherwise stated these are over-bark log volumes. It should be notedthese do not take into account losses during conversion to sawn timber, plywood, pulp SPECIESThe Australian eucalypts have been among the most widely used and successful plantationtrees. Only a few 500 species have potential in industrial plantations (FAO 2000). Jacobs6(1981) suggested that a MAI of 10-15 m ha- yr- was commonly obtained from the largescale plantations, but more recent experience suggests that on many sites faster growth ratesare possible (Appendix 1).

9 Eucalypts are recognized as the some of the fastest growing dominant trees on fertile sites at Gogol, near Madang, Papua New Guinea reached 38 min height and 39 cm in diameter breast height over bark (DBHOB), at three years of age; thiswas equivalent to an MAI of 80-90 m ha- yr- (Eldridge et al. 1993).These faster growth rates result from using careful site selection, intensive cultural practices,selection of the best species and provenances, and genetic improvement (see also WorkingPapers FP/3 and 4). Small sample plots of eucalypt aged 6-8 years in East and West Africa,Brazil, and Papua New Guinea have had MAIs up to 100 m ha- yr.

10 More typical of fast growing stands, however, is the productivity of South Africa eucalypts(mainly Eucalyptus grandis and its hybrids). There the average productivity is 21 m ha- yr- (MAI of 15-55 m ha- yr- ) (Du Toit et al. 1998).In Brazil, where there are about four million hectares of eucalypts, the MAI is commonlybetween 5 and 35 m ha- yr- , on rotations from 5 to 21 years. The majority of theseplantations are E. grandis grown on 5-10 year coppice rotations (Turnbull 1999). Intensivebreeding and silviculture has been reported as raising MAI from 33-70 m ha- yr- for and E.