Monthly averaged soil matric potential and re-scaled average wood properties in the irrigated and non-irrigated plots from July 2005 to May 2007. Soil matric potential reached a minimum in summer 2006 in the non-irrigated trees and in winter 2006 in the irrigated trees (a). Wood density increased in response to high water deficits in non-irrigated trees in summer 2006 and in irrigated trees in winter 2006 (b). Microfibril angle declined in winter 2006 in irrigated trees and increased in late 2006/early 2007 in non-irrigated trees (c). Fibre radial diameter decreased in non-irrigated trees in summer 2006 and in irrigated trees in winter 2006 (d). Bars/points show mean ± standard error.