Effects of plant spacing and season on growth of Melaleuca alternifolia and yield of tea tree oil

Abstract

A plant spacing experiment with the tea tree oil species, Melaleuca alternifolia was carried out at Castle Hill, New South Wales, from 1970 to 1979. The study compared the response to three within-row spacings and measured the effects of seasons over seven harvests. The planting patterns tested were 1.22 x 1.22, 0.61 and 0.305 m. For all years there was an average increase in leaf and oil yield of 93% (2.9 l/ha and 46 l/ha, respectively) in the highest population (26 908 trees/ha) compared with the lowest (6727 trees/ha). Large differences in growth rate and oil yield occurred between years. I conclude that M. alternifolia is amenable to cultivation for tea tree oil production, plant spacing is an important factor in its management and optimum population exceeds 27 000 trees/ha.