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GRAPE GRO WING Grower's Handbook" (UC ANR Publication 3338) summarized considerable experimentation and practices that are now used by winegrowers all over the West Coast, Europe and Australia. Building organic matter The importance of building organic matter has been well documented by soil scientists since the 1930s but somewhat forgotten as intensive tillage and soluble chemical fertilizers were introduced to agriculture after World War II. It is the core belief of organic farming in terms of importance to crop health and vitality. By the end of the 20th Century, the need for a solution to reducing solid waste in landfills resulted in experimentation with making compost by many growers, wineries and municipal waste management companies. The use of compost in vineyards and agriculture is becoming much more common in the United States, and it serves another purpose as well—sequestering greenhouse gases. The earth's soil has the potential to sequester five times the amount of carbon dioxide as is contained in the atmosphere. Between the use of compost and cover cropping, soil carbon content can be increased significantly in a fairly short period of time (if tillage is reduced, especially in hotter climates.) This is turn can help to improve water infiltration and storage, soil quality, soil biological activity and soil fertility. Creating biodiversity and habitat Organic growers realized early on that there were many opportunities for biological control of some of the common vineyard insect and mite pests. Creating a place for beneficial predators and parasitoids to live was as simple as planting cover crops, leaving native shrubs and trees on the edge of Organic winegrape growers such as Ceago Vinegarden use spaders to incorporate cover crops without harming soil structure. their vineyards, planting hedgerows and generally moving away from the "completely clean" look. Once again, these were not new ideas: Since the 1960s, many integrated pest management (IPM) practitioners were encouraging growers to get off of routine spraying by the calendar and actually look and see what was happening in their vineyards before spraying. They also encouraged a move away from potent broad-spectrum insecticides. Organic growers showed that nature could control many common vineyard problems, and spraying wasn't always needed. The materials that were available for organic growers were pretty "soft" and didn't negatively impact beneficial insects. Winegrowers farming sustainably have also followed this principle, and now growers apply insecticide sprays much less frequently than in the past. Even in the case of a new exotic pest, pest-management practices are focused on targeting the specific species if possible and not harming beneficials. For instance, the most common pesticide used in controlling the European grapevine moth is Bacillus thuriengensi, a bacterium that attacks moth larvae but is harmless to many predaceous wasps, generalist predators and other creatures. Similarly, pheromone confusion and a new biological control agent are being experimented with to control vine mealybug. Integrated approaches to controlling powdery mildew Organic growers realized that relying simply on sulfur dusting or wettable sulfur for powdery mildew control wasn't the perfect system—dusting could cause mite flare ups (almost impossible to control in an organic vineyard), and too much residue of wettable sulfur could result in reduced odors in the wine. Leaf pulling, shoot positioning and other canopy-management practices became common as part of the organic powdery mildew-control program. In the early 1990s, the Fetzer family installed the first Adcon System in California on their holdings and began using the UC Davis Gubler-Thomas Powdery Mildew Index to help improve the timing of their sulfur applications. In some cases, they reduced the number of sulfur dustings from 10 to three applications per season by using the model to guide their application decisions. Many other growers soon adopted this 68 Wines & Vines FeBRUARY 2012