Issue link: http://read.dmtmag.com/i/72545
VINEYARD developers who seek to purchase land and establish vineyards in a specific region. For a landown- er who already has acreage, the model can assist in determining the most suitable planting locations on the property, and the most suit- able varieties to plant. The model can also be used on a comparison basis, to look at established vine- yards that are producing quality grapes, determine the environmen- tal factors specific to these sites, and then locate sites in the appella- tion with similar conditions to plant vineyards. Using the digital data with com- puter graphics and mapping capa- bilities, different data layers and environmental variables can be broken out and looked at individu- ally, or overlaid to look at two or more priority variables and where their locations intersect. Although the system is not a substitute for onsite field evaluations, Skinner said, "This allows you to look at an area in different ways for dif- ferent characteristics as a start- ing point, without spending weeks on the ground gathering data and digging holes for soil pits over a wide area." He further explained, "These maps and information point out those areas that are potentially good for vineyards, then you can go out on the ground and fine-tune the information from there." Maps and graphics at the region- al and appellation level currently are scaled with a maximum pixel reso- lution of 30 meters by 30 meters. Optimal Suitability Cabernet Variable s Elevation (m) Slope (%) Aspec t Soil Depth to Any Restrictive Layer (cm) Soil Drainage Rock Fragments (%) Soil pH Soil OM% Available Water Capacity (cm/cm) Surface Texture GDD FF D Land Use Field scale maps generated with data from higher-density sampling can be accurate to a scale of 3 meters by 3 meters. As examples of how the model Variable s can be used for specific varieties, Terra Spase has developed optimal suitability ranges for cabernet sau- vignon and chardonnay based on several environmental factors. Skin- ner noted that chardonnay tends to do better in deeper soils with better water-holding capacity; whereas, cabernet sauvignon grows well on shallower, well-drained soils, and on slopes up to 10%. The chart above illustrates optimal suitabil- ity factors and ranges for cabernet sauvignon in Lake County. The variables used in the index Elevation (m) Slope (%) Aspec t Soil Depth to Any Restrictive Layer (cm) Soil Drainage Rock Fragments (%) Soil pH Soil OM% Available Water Capacity (cm/cm) Surface Texture GD D FF D Land Use can be adapted based on region- al differences and concerns. For example, precipitation is not includ- NEW & USED UNITS AVAILABLE All Major Credit Cards Accepted COLD SHOT CHILLERS® • Low Temperature Glycol Chillers • Custom Designed Cooling Applications from 2 to 100 Tons • Most Machines Shipped in 2 Weeks or Less • 5 Year Compressor Warranty • Providing Cooling Solutions for 30+ Years • Free Technical Support 24/7/365 800-473-9178 • 281-227-8400 FAX: 281-227-8404 50 VINEYARD & WINERY MANAGEMENT JULY - AUG 2012 www.waterchillers.com Optimal Suitability Chardonnay Optima l Range 450-750 3-10 E S >91 Well Drained <15% 5-7 1-3 <0.1 3000-3500 0 CL, L >18 Pasture/Hay, Grassland ed in the TSVS model for Lake County, because rainfall is minimal during the growing season. How- ever, for locations in the Midwest that receive significant rain during the summer, this variable could be a site factor that influences planting suitability, and rootstock and vari- ety choices. Skinner also indicated the model could be used to look at potential pest pressure for differ- ent sites. "If an area was within a pest's known range, we may be able to incorporate its potential occurrence based on degree-day data that correlates to the pest's seasonal emergence and life cycle," Skinner said. Optima l Range 450-750 0-5 N >91 Somewhat Poorly Drained <5 6-8 2-4 0.16-0.22 CL, C 2500-300 0 >18 0 Pasture/Hay, Grassland MODEL FOR NEW GROWING REGIONS Skinner's focus for the model is for locations where there is interest in, and potential for, planting new vineyards. He started with Men- docino and Lake counties, locations in the North Coast where potential new vineyard acreage still exists, as compared with Napa County, where the most suitable (and avail- able) vineyard locations are already planted or known. Based on his travels through- out the United States, Skinner observed, "There is a lot of inter- est in planting wine grapes in many parts of the country, but not a lot of information is available for potential growers in many locations. There is a place for more information, partic- WWW.VWM-ONLINE.COM