Volume 4 No.6, June 2014 ISSN 2224-3577 International Journal of Science and Technology ©2014 IJST. All rights reserved http://www.ejournalofsciences.org 118 Does heartwood formation early process in Beninese coppice teak stands? Armand Sèdami Igor Yêvidé 1 , Eude O. A. Goudégnon 2 , Jean Cossi Ganglo 1 , Madjidou Oumorou 2 , Adolphe Tchéhouali 2 , Charles De Carnnière 3 1 Laboratory of Forest Sciences, Faculty of Agronomic Sciences, University of Abomey-Calavi, 01 BP 526, Cotonou, Benin. 2 Ecole Polytechnique d’Abomey-Calavi, University of Abomey-Calavi, 01 BP 2009, Cotonou, Benin. 3 Université Libre de Bruxelles, Ecole interfacultaire de bioingénieurs, service: Ecologie du paysage et Systèmes de production végétale, Avenue F. D. Roosevelt 50 CP 169, B-1050 Bruxelles. ABSTRACT Teak heartwood formation process is less documented especially in Benin where the species has been widely established by farmers under coppice regime and provide woods largely used by consumers in cities. The objectives of this study were to determine the beginning age of heartwood formation process in coppice teak plantations and the impact of age and plant communities on heartwood percentage. Based on 54 discs sampled from plantations of divers ages in the two widest plant communities spread in Atlantic department, percentages of heartwood were assessed and compared as function of trees age and plant communities. Our findings revealed that heartwood formation begins early and that the coppice regime tends to quicken the heartwood formation process. The percentage of heartwood diminishes along tree from the base to the crown base while generally it increases with the age once the process began. There was statistically no difference between heartwood percentages formed at different ages. But at the same age significant difference exists between plant communities. Sound place choices for coppice teak stands establishment could help farmers to improve the physic-mechanical, chemical and biological characteristics of their woods as they depend on heartwood formation and percentage. Keywords: Duramen formation, Heartwood percentage, Coppice teak plantation, Plant communities, Benin I. INTRODUCTION T eak (Tectona grandis L.F) is among the first forest trees species used under tropic [1]. It is a fast grown species holding exceptional wood qualities and highly appreciated on the international market. As being multipurpose wood, teak is used in carpentry, joinery, furniture, cabinet making, veneers and boat construction [2; 3]. As result of its good wood properties, teak has been widely planted and its rotation length shortened to supply the increasing needs of consumers. Studies were carried out to assess the impact of growth rate, rotation length, stand age and ecological zones on the overall wood characteristics. They reported that teak could produce timbers of optimum strength in relatively short rotation of about 20-years [1]. The process of heartwood formation begins early at 7-years-old in Togolese teak plantations and wood density was significantly correlated to trees age [4]. The same authors have found significant difference of modulus of elasticity between juvenile and adult wood and influence of ecological zones on teak wood properties. This latter finding has been supported by another study which has revealed impact of ecological factors on wood biophysical properties in Togo [5]. In Benin, teak is grown at shorter rotation length of about 6-years by farmers in their private plantations whence they supply consumers with pools for construction and other purposes [6; 7; 8]. The scope of uses made of private teak woods led us to assume that contrary to seeds-based plantations, heartwood formation in Beninese coppice teak stands is an early process. This study aims therefore to: (i) determine the beginning age of heartwood formation in coppice teak stands; and (ii) assess the impact of age and plant communities on heartwood percentage. II. MATERIALS AND METHODS Study Area The study was carried out in five communes located in the