Variation in Heartwood Formation and Wood Density in Plantation-Grown Red Sanders (Pterocarpus santalinus)

Abstract

Pterocarpus santalinus L. f. (Red Sanders) is narrowly endemic to the Seshachalam, Veligonda, Lankamala and Palakonda hill ranges in Andhra Pradesh. The wood and wood products of Red Sanders continue to be in high demand and are traded internationally in large volumes that find use in the musical instruments, furniture, handicrafts, cosmetics, medicine and food industry. Over exploitation without commensurate replenishment of natural stands and illegal logging has posed a severe threat to the very existence of this precious timber species and classified as globally threatened in the IUCN Red List. Good-quality heartwood of Red Sanders is illegally traded and fetches very high price in the global market. As harvest of heartwood from natural population may not be sustainable, any future plan of harvest of Red Sanders wood and export should be from cultivated sources. About 5000 ha of plantations of Red Sanders exists in various states in South India. Little information is available about the quality and quantity of heartwood formation in plantations compared to natural populations. In this backdrop, the current study was conducted to evaluate the variation in heartwood, sapwood and bark content, and wood density of plantation-grown Red Sanders trees of various age classes located in various places. The core wood samples from various locations were collected using increment borer based on standard sampling procedure. The heartwood, sapwood and bark content were measured as a percentage of the cross-sectional area at breast height. Wood density was determined using core wood samples taken at breast height of the tree. The variation in heartwood content and wood density of Red Sanders were found to be influenced by the age and size of the trees.