Non-destructive sampling of Indian sandalwood (Santalum album L.) for oil content and composition

East Indian sandalwood, Santalum album, is renowned for its fragrant heartwood. Current methods of heartwood oil assessment of standing trees remain largely untested and unreliable. Core sampling of 22 S. album trees at fixed heights followed by solvent extraction of core samples and subsequent analysis was correlated to distilled yields of wood from the same trees. Oil contents of 10-year-old sandalwood trees generally decreased exponentially up the height of the tree, with considerable variation amongst the population. From these trends, core sampling was used to estimate oil yields but large discrepancies existed, and only relative differences could be described. Gas chromatography yielded the most informative results for each core, particularly that the oil composition varied little at 30 cm or at 100 cm, however, there was a slightly higher proportion of sesquiterpene hydrocarbons in samples taken from 100 cm than those from 30 cm. The proportion of sesquiterpene alcohols was generally higher in 30 cm wood cores than in 100 cm samples.