wine grapesthe Altieri Lab Agroecology Research Group: Vineyard Agroecology

Goal of Conservation Biological Control Research    

    The goal of our research project is to scale-up agroecological approaches that break vineyard monoculture structures with cover crops and/or hedgerows and corridors, enhancing biological control (Altieri et al, 2005). We have been repeatedly approached by wine grape growers to assist them in re-designing their vineyards to manage insect pests ecologically. This demand stems from the fact that despite the use of Integrated Pest Management  (IPM) -- an ecosystem-based strategy that focuses on long-term prevention of pests or their damage through a combination of techniques such as biological control, habitat manipulation, modification of cultural practices, and use of resistant varieties -- many vineyards continue to experience high levels of pest pressure, an expected trend in monocultures that lack functional biodiversity (Gurr et al, 2004).

    This project is unique in its participatory nature. Farmers are actively involved in the implementation of the designs as well as the monitoring, allowing the testing of a suite of agroecological strategies in several environments. At each participating vineyard, a 1 acre experimental plot is established to assess the effectiveness of several designs on soil quality indicators and populations of insect pests and natural enemies. Strategies to enhance plant biodiversity include: (a) summer cover crops -- Common Buckwheat between vine rows and Sweet Alyssum under the drip line between vine plants and; (b) enriched hedgerows surrounding the vineyards. Diversification will be complemented with organic soil fertilization treatments to enhance organic matter content and soil fauna. We expect grapes grown in soils with high organic matter and active soil biology to exhibit lower abundance of insect pests (Altieri and Nicholls, 2003). Summer cover crops effects on natural enemies and pest populations, as well as influence of selectively planted hedgerows on foliage and soil fauna are being assessed using well tested methods (Nicholls et al, 2000, 2001; Daane and Costello, 1998). Effects of soil fertility management treatments on soil invertebrate fauna considered to be sensitive indicators of soil health are being measured using known monitoring techniques (Anderson and Ingram, 1993).

Agroecological Participatory Research

    All farmers involved  in the project practice organic agriculture or follow IPM guidelines, but still rely on mono-cropping  dependent on external inputs. Farmers are motivated to move beyond input dependence and want to establish biodiverse designs. We will tailor site specific system designs for each farmer allowing them to compare trends between experimental plots and their current management systems. Farmers will be able to interpret the ecological processes and interactions that underline such observed processes. As farmers become increasingly confident on the new practices they will progressively increase the area under agroecological management.  Understanding how organic fertilization improves plant health may lead  to new  ways to integrate pest and soil fertility management promoting synergies between cover crops, soil invertebrate bioindicators, natural enemies and overall vineyard health. Conversion to agroecological management will enhance farmers’ income by opening new market opportunities and attracting a more specialized type of agroecotoursim. The ecological principles underlying successful designs can be scaled-up to reach hundreds of other producers, facilitating the transition of California’s wine regions to greater ecological and social sustainability.

Outreach

    Participating growers  play a key role in determining cover cropping and organic fertilization practices to be used in each experimental plot, and also in defining plant composition and location of hedgerows. Managers and a team of farmworkers  collaborate  in the monitoring of insect populations, soil and crop health parameters. Our group conducts several training sessions (in Spanish) for a group of farm laborers that are becoming crucial monitoring scouts. Producers also have a key role during field days as disseminators of the best practices among other farmers in the region. We expect producers to have a major input into the written materials produced so that they are relevant and farmer friendly educational tools.
href="http://www.cnr.berkeley.edu/site/index.php">