V. riparia
This species of grape is the only one of the three grapes given that is resistant to phylloxera, which could potentially increase its ability to survive in certain areas. This specific species if more rare than the other two species examined and can produce such wines as Martin, Grand Glabre, and Scribner. This species cannot survive on calcareous soils, but is able to survive frost, low winter temperatures, short growing seasons, and reasonable amounts of rainfall. It would therefore appear to have a high potential for survival in the GVRD. These factors were used to consider the specific constraints and factors of this species for the multi-criteria evaluation.
Constraints
The climatic zone for this species in the GVRD was consider to be Eastern dry ( a value of 2) because of its ability to survive cooler temperatures. The Climate image file was reclassed to give a value of 1 to this zone and a value of 0 to all other zones.
The soil textural class for this species was till because it was the least likely to contain sedimentary rocks and soils that are calcareous. The Soil Texture image file was given a value of 1 with every other class receiving a value of 0.
Factor
Till is usually produces a highly drained soil and therefore this species could potentially be produced closer to rivers and water bodies. The Decision Wizard values to make the water distance file to a fuzzy image are as shown.
