Abstract
The scarcity of timber to supply the wood-based industries is one of the prevailing problems worldwide. Tree plantations are the remaining solutions to subdue the shortage of raw materials, at the same time sequester atmospheric CO2 in its biomass to reduce global warming. Planting Big-leaf mahogany (Swietenia macrophylla King) contributes valuable economic inputs to small tree farmers in the Philippines. However, the occurrence of lumber defects during processing due to growth stresses reduces the potential value of timber. This study aimed to examine the differences of surface growth stresses and wood properties of an 8-year-old BL mahogany from six landrace provenances in two progeny trial sites, Butuan and Cagayan de Oro in the Philippines. The longitudinal released strains of the surface growth stress (SRS) were not significantly different among six landrace provenances and between two trial sites. The SRS were not significantly related to diameter at breast height (DBH) in both trial sites. The high level of negative SRS was observed in some tested trees with small diameter in both trial sites, which was attributed to the tension wood formation in an irregular-shaped stem. The xylem density (XD), average microfibril angle in the secondary cell wall (MFA), vessel element length (VL) and vessel element width (VW) had no significant differences among six landrace provenances. In terms of trial sites, Butuan trial site gave high lateral growth DBH, high XD, longer fiber length (FL) with a narrow fiber width (FW) and smaller MFA as compared to the Cagayan de Oro trial site. It was observed that an 8-year-old BL mahogany plantation with small-diameter trees exhibited high SRS, low XD, small FL, wide FW and large MFA, which are passively considered as properties of juvenile wood.
Highlights
The Big-leaf (BL) mahogany (Swietenia macrophylla King) is one of the world’s most high-valued timber species
Some wood properties [xylem density (XD), tangential and radial shrinkage, modulus of elasticity (MOE) and modulus of rupture (MOR)] of Big leaf (BL) mahogany differ between natural forest and plantation forest [7]; these findings may influence the specific wood utilization of planted BL mahogany
Lateral growth rate—diameter at breast height (DBH) Comparing DBH of all planted trees among six landrace provenances and between two trial sites (Fig. 2), the result showed that DBH among six landrace provenances has no significant difference (Table 3), while the difference between two trial sites was highly significant
Summary
The Big-leaf (BL) mahogany (Swietenia macrophylla King) is one of the world’s most high-valued timber species. Some countries and/or some private bodies have invested in plantations in order to ensure a sustained production of high-value timber [1, 2]. BL mahogany grows naturally in Belize, Bolivia, Brazil, Colombia, Costa Rica, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Peru and Venezuela. It is nearly extinct in Ecuador, Colombia, Panama and Costa Rica; close to commercial extinction. Some wood properties [xylem density (XD), tangential and radial shrinkage, modulus of elasticity (MOE) and modulus of rupture (MOR)] of BL mahogany differ between natural forest and plantation forest [7]; these findings may influence the specific wood utilization of planted BL mahogany
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
