The major goal of the Soil Assessment for Vineyard Design is to provide sufficient information on the soil resource to design a vineyard layout based on blocks of highly uniform soil properties that will allow for the production of the highest quality fruit for that particular site. Since both water and nutritional availabilities are the major factors contribution to vine growth and vigor, implicit in this design strategy is the desire to provide blocks that produce fruit of extremely high quality from highly uniform vine growth and uniformly ripe fruit. Great wines are not made with grapes that have a broad spectrum of ripeness. The report of this analysis will include a calculation of total available water to various depths to allow for precise recommendations for block boundaries, tillage depth, tillage implements, pre- and post tillage soil amendments, row widths, vine density, row orientation, trellis type, varieties, clones, and rootstocks. The report will frequently have up to 40 maps and charts that allow the reader to visually see how the soils' physical and chemical characteristics change across the landscape. These reports are sufficiently detailed to allow a vineyard developer to initiate vineyard establishment (permitting, irrigation, land preparation, nursery ordering, etc).
Both of these products rely on the soil pit evaluation as the major data source. Each pit (5 ft depth) will have a soil profile log recorded that quantifies and qualifies many of the soils properties of each horizon observed. These soil properties include soil color, texture, rock (abundance, size and type), soil structure and particle aggregation, soil hardness, soil porosity, root density, color and quantity of mottling, approximate moisture content and any extraneous comments (presence of cementation, signs of poor drainage, presence of mad-made debris).
All soil pits and other important locations (wells, pipe, structures) are registered with a GPS unit and these coordinates are provided on the profile logs and the maps created for the project report.
Typically the different soil horizons will be sampled for chemical analysis of most plant nutrients and other toxic and/or influential elements. Samples can also be taken for analysis for nematode (parasitic worms that infest winegrape rootstocks).
Water sources may also be sampled for irrigation quality analysis.
All of the aforementioned data will be presented in a written report that will first provide the importance of each soil characteristic to winegrowing, and then discuss the specific values of the soil characteristic measured for this report, and any recommended treatments if the value is undesirable. Reports will be delivered in both paper and Adobe PDF format.