John S. Larmour

Eucalypt Taxa for Low- to Medium-rainfall Farm Forestry in South-Eastern Australia

Summary Enhanced knowledge of on-farm forestry opportunities in the low to medium (500–750 mm) mean annual rainfall zone of south-eastern Australia is needed to maximise commercial and environmental benefits. Key research issues include species and provenance selection, site preparation and silviculture. As part of the ‘Heartlands Initiative’, CSIRO established several taxa evaluation trials in southern NSW and northern Victoria (within the Murray Darling Basin) in 2002. Results from four of these trials, comprising 16 taxa, are presented. Large differences in survival were evident amongst sites and species. Mean survival after 5 y was highest (89%) at Coomalong (near Violet Town, north-eastern Victoria), followed by Brooklyn West (near Wagga Wagga, NSW; 85%), Byawatha Hills (near Springhurst, north-eastern Victoria; 76%) and Koora (near Holbrook, NSW; 54%). Mean stem diameter and calculated stem volume at 5 y were greatest at Coomalong, but mean height was similar at the three sites. Survival of the commercial Eucalyptus camaldulensis × E. globulus hybrid clone, E. cladocalyx, E. argophloia and E. camaldulensis was consistently high. Eucalyptus camaldulensis × E. globulus hybrid clone had the best growth across all sites, followed by E. benthamii, E. botryoides and Corymbia maculata. Best tree form was achieved by E. camaldulensis × E. grandis, E. camaldulensis × E. globulus, E. benthamii, C. maculata and C. variegata. Growth of E. crebra was consistently poorest, with E. occidentalis also having slow growth and poor form. Selection of suitable taxa and best-practice establishment and silviculture are critical to establishing good plantations on these sites.