This evaluation is geared to assess land already planted to vineyards that is for sale and the buyer or seller needs to determine the soil and vine resources on the land. The evaluation will include an analysis of the planted area, potentially plantable area, soils types and current fertility, soil pests, vine health and disease, as well as, verification of varieties and rootstocks.
This assessment is recommended for buyers and sellers of land to get an overview of the soil resource and the suitability of the land for winegrapes production. The assessment identifies and quantifies the major soil resources such as the soil type, soil fertility, soil chemical hazards, water holding capacity, amounts and depths to rock. Based on the assessment, recommendations as to the suitability of the land will be made, as well as, general recommendations concerning development of the land into vineyards so a potential developer can calculate the cost associated with land preparation and vineyard establishment. This analysis is frequently coupled with a slope and aspect analysis to allow for calculation of areas of land that have slopes less than regulatory limits and are thus legally plantable. The soil sampling density of this type of study is generally not sufficient to discern transition zones in changes in soil properties and thus is not sufficient for vineyard block design.
The major goal of the this assessment is to provide sufficient information on the soil resource to design a vineyard layout based on blocks of highly uniform soil properties. Since the availability of water and nutrients are the major factors contributing 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 fruit ripeness. Great wines are not made with grapes that have a broad spectrum of ripeness.
The assessment 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. 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.The report will frequently have up to 40 maps and charts to visually see how the soil 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).