Seasonal variations in the leaf fall and quality of the leaves of four Australian fodder trees.

Abstract

The effect of season of year on the extent of leaf fall, and the nutritive value of plucked and fallen leaves of four tree species growing in a Belah-Rosewood woodland in western New South Wales was examined over four years. Leaf fall was not correlated with rainfall but tended to a maximum in summer and autumn. There were substantial differences between species in the extent of leaf fall and in nutritive value of the leaves. Fallen leaves were of lower nutritive value than leaves plucked from the trees. The most digestible species, Wilga, yielded 21 kg/ha of leaf fall per year, whereas the least digestible, Belah, yielded 113 kg/ha. The low digestibility of the most common tree, Belah, renders it of little value as a drought reserve, but the less abundant Wilga and Rosewood are of value in supplying protein and energy in drought conditions. The amount of phosphorus returned to the soil via leaf fall would be insufficient to enhance herbaceous production beneath the trees.