Precision Viticulture Research

Susan Hubbard

Precision Viticulture Research

Susan S. Hubbard - MS Geophysics, PhD Engineering, UC Berkeley (1999) and Professional Certificate in Winemaking and Viticulture UC Davis (2009).The ability to optimize winegrape production necessitates an understanding of the factors that influence their spatial and temporal variability. The majority of precision viticulture has focused on investigating the link between winegrape parameters and above-ground factors, such as the training, cultivation, and harvest timing of the grapes. Soil properties, which control water drainage, are also critically important to winegrape quality, although not as much emphasis has been given to investigating the role of soil properties on winegrapes as has been given to above-ground factors. This is partly due to that fact that heretofore, most soil characterization has been performed using invasive methods (such as by digging backhoe pits or collecting point measurements). These techniques are invasive and laborious, and yet still provide information at a single point in time/space only, which is often insufficient to capture the field-scale variability in soil properties that are observed in vineyards. Because vineyards are not typically planted nor managed with a good understanding of natural soil property variations, spatial variation in winegrape quality is common, even when all farming practices are constant throughout vineyard blocks.

My precision viticulture research focuses on two areas:

  1. Interpretation and integration of non-invasive and spatially exhaustive geophysical data with sparse direct soil measurements to estimate vineyard soil parameter spatial distributions over space and time. For example, we have investigated the applicability of ground penetrating radar (GPR) methods to provide very high resolution estimates of near surface water content within several California vineyards. Comparison of our geophysical estimates with conventional measurements of water content, soil texture and plant vigor measurements has illustrated that the estimates are accurate and reliable, and that water content, soil texture and plant vigor are correlated.
  2. Use of geophysically-obtained information, integrated with micrometerological information using statistical and water balance modeling approaches, to guide optimal development of vineyards. We have developed statistical methods and assessed the benefit of utilizing a wide variety of surface geophysical, soils, climate, digital elevation, and plant data to guide the optimal development of vineyards (such as the row and vine spacing and irrigation parameters). This approach honors the natural variability of the site, and permits uniform development of winegrapes within vineyard blocks and efficient use of irrigation water. These approaches are also useful for delinating and determining the cause of poor performing vineyard areas.

Publications and Presentations

Precision Viticulture Press Releases