Ecology of Sandalwood (Santalum Spicatum) Near Paynes Find and Menzies, Western Australia: Size Structure and Dry-Sided Stems.

Abstract

Population size structure of sandalwood (Santalum spicatum) was studied on four pastoral leases near Paynes Find and Menzies, in semi-arid Western Australia. Stem diameter, height, height to crown and the orientation of dry-sided stems were recorded for 1017 individual sandalwood. Populations of S. spicatum at Paynes Find contained only mature trees, indicating no successful recruitment for at least 30 years. In contrast, populations of S, spicatum at Menzies had a high proportion of seedlings and saplings. Crown measurements of mature S. spicatum trees indicated high grazing intensity at Paynes Find: mean height to crown at Paynes Find (147-148 cm) was significantly higher than Menzies (92-94 cm). Dry-side percentage differed significantly between directional faces, consistent with sun damage. Highest mean dry-side percentages were on stem sides facing the sun between midday and late afternoon: west, north-west, south-west and north. This directional pattern was the same between pastoral leases, and there was no interaction between pastoral lease and dry-side direction. Mean percentage of mature trees with a dry-sided stem was also significantly higher at Paynes Find (76-82%) than at Menzies (42-46%). Significantly less foliage low to the ground on mature trees at Paynes Find may have exposed the stems to more sun damage. Land systems did not significantly influence dry-side direction on Burnerbinmah or Goongarrie. No S. spicatum seedlings or saplings had a dry-sided stem. Key words: Santalum spicatum, size structure, dry-sided stems