Geology and Wine 10: Use of Geographic Information System Technology to Assess Viticulture Performance in the Okanagan and Similkameen Valleys, British Columbia

The complex geological history of the Okanagan and Similkameen valleys in British Columbia has created a wine growing region by way of diverse bedrock, soils, terrain and climate. Although wine grapes have been grown in the area for many decades, a recent conversion of vineyards to predominately Vitis vinifera varieties, and the subsequent world recognition of wine quality, suggests that there is further potential to improve wine quality through fine-tuning of grape varietal choices and vineyard management techniques. A geographic information system (GIS) application has been developed to study the relationships among site conditions, management practices and vineyard performance including fruit and wine quality. The production area was divided into six regions based on landform and climate: 1. Kelowna, 2. Penticton, 3. Vaseaux - Oliver, 4. Golden Mile, 5. Black Sage - Osoyoos, and 6. Similkameen. The complement of grape varieties planted varies among the regions. Comparisons of regional patterns of varieties planted, and medals received, have revealed significant regional differences in varietal suitability. Although most of the vineyards are sited on coarse-textured soils, comparisons of the distributions of all and medal-winning vineyard blocks among soil textural classes have revealed that quality wine grapes are grown on a broad range of soil types within, and among, the six regions studied. Loamy soils appear to be especially suitable for producing quality wine grapes in the Okanagan and Similkameen valleys. SUMMAIRE L'histoire geologique complexe des vallees d'Okanagan et de Similkameen en Colombie-Britannique a cree une region vinicole en reunissant divers socles rocheux, sols, terrains et climats. Bien que le raisin de cuve ait ete cultive dans la region depuis plusieurs decennies, une conversion recente aux varietes de Vitis vinifera , et la reconnaissance mondiale de la qualite de ses vins qui s'en est suivie, permet de penser que la qualite des vins pourrait encore etre ameliorer par le choix de varietes de vignes et l'amelioration des techniques de production. Une application d'un systeme d'information geographique (SIG) a ete mise au point pour etudier les relations entre les caracteristiques des sites, les pratiques de gestion, et les performances du vignoble, dont la qualite des fruits et du vin. La zone de production a ete subdivisee en six regions selon la forme du relief et le climat, soit : 1. Kelowna, 2. Penticton, 3. Vaseaux-Oliver, 4. Golden Mile, 5. Black Sage, et 6. Similkameen. Le complement des varietes de raisin plantees varie selon les regions. Les comparaisons d'arrangement des varietes plantees et des medailles recues ont mis au jour d'importantes differences regionales quant aux varietes les mieux adaptees. Bien que la plupart des vignobles croissent dans des sols legers, les comparaisons des distributions des parcelles en fonction des types de texture des sols et des medailles recues ont montre que des vignes de qualite sont cultivees sur une grande variete de types de sol a travers les six regions etudiees. Les sols loameux semblent particulierement convenir pour la production de raisin de cuve dans les vallees d'Okanagan et de Similkameen.