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WINEMAKING have great potential to affect vineyards. In hindsight, it should not be too surprising that eucalyptus leaves or bark falling from trees can be blown some distance by the wind to lodge in grapevine canopies, and from there be picked with the harvest to affect the wine. This source had not been previously considered, however, with popular thinking that airborne transfer of the eucalypt essential oil volatiles was probably the main avenue. Even though the leaves are dried and brown within vine canopies, they clearly can influence the character of a wine and are of greater importance to ultimate 1,8-cineole levels in a wine than simple aerial transfer of the volatiles from the trees to the berry skins. For winemakers, this presents a range of management options in terms of minimizing or maximizing "eucalypt" characters. Wine producers may choose to ferment grapes from vines growing near eucalyptus trees separately and use this wine as a blending option; they can hand pick those rows closest to trees; or they can ensure that minimal MOG is included in machine harvest bins of grapes. Sorting tables, whether manual or automated, also would be effective but obviously more costly. Adjusting machine harvester settings so that less non-grape material is picked, especially in rows closest to trees, would be another straightforward strategy. By paying closer attention to the volume of grape leaves, stems and eucalyptus leaves or bark in their ferments, winemakers can exert greater control over the wines they are seeking to create. Overall, the results described here give winemakers practical ways to control 1,8-cineole concentrations throughout vineyard and winery operations. The closeness of grapevines to eucalyptus trees has a conclusive effect on 1,8-cineole concentrations in wine, and the presence of MOG can significantly influence 1,8-cineole levels. Both factors have a major impact on sensory characteristics. Enhancing or reducing "eucalypt" characters is no longer a case of pure chance or serendipity, and winemakers are in a much stronger position to take greater control of 1,8-cineole and adjust eucalyptus character to create wines that express their terroir with market appeal. The authors wish to acknowledge numerous Australian wine companies for the generous donations of grape and wine samples, and the contributions of numerous colleagues in particular Drs. Mark Sefton and David Jeffery for their contribution to this work and assistance in the preparation of this article. This work was supported by Australia's grapegrowers and winemakers through their investment body, the Grape and Wine Research and Development Corp., with matching funds from the Australian government. References 1. erve, E.; Price, S. and Burns, G. (2003) In Proceedings VIIème SymH posium International d'Œnologie, Actualités Œnologiques, Bordeaux, Lonvaud, A.; De Revel, G. and Darriet, P. (Eds) Tec & Doc; Lavoisier: Paris, France; 598-600. 2. arina, L.; Boido, E.; Carrau, F.; Versini, G. and Dellacassa, E. (2005) F Terpene compounds as possible precursors of 1,8-Cineole in red grapes and wines. J. Agric. Food Chem. 53:1633-1636. 3. apone,D.L.; van Leeuwen, K.; Taylor, D.K.; Jeffery, D.W.; Pardon, C K.H.; Elsey, G.M. and Sefton, M.A. (2011) Evolution and occurrence of 1,8-cineole (Eucalyptol) in Australian Wine. J. Agric. Food Chem. 59:953-959. 4. sidacz, P.; Geue, J.; Bramley, B.; Siebert, T.E.; Capone, D. and FranO cis, I.L. (2010) Exploring the influence of pepper, eucalyptus and smoky flavour compounds on consumer preferences of red wines. AWRI Tech. Rev. 189:8-11. Win es & Vin es F EB RUA RY 20 13 57