Pesticide representatives apparently cooperate with this effort. Pesticides or herbicides that are toxic to a weed or fungal disease may not be toxic to humans. The higher the LD50, the less toxic the substance. Member-growers are conscious of human and environmental safety when deciding if a pest problem needs treatment and when choosing a pesticide to use when treatment is required. The product they use most is sulfur, which is often applied as dust.
Sulfur is approved for application in certified organic grape production.
The Sonoma County Grape Growers Association encourages the use of alternatives to the soil fumigant methyl bromide for preventing nematodes and oak root fungus. None of the growers interviewed is eager to fumigate, and many said they never do. Those that do fumigate typically do so only when nematodes or oak root fungus are found in the soil. The pressure to find economically viable alternatives to methyl bromide use is mounting as the fumigant is to be phased out by 2005. Farmers are thoughtful in their use of pesticides and try various solutions to see what will work on the pest problem with the least environmental impact.