fumigation, the viticultural practice of fumigating vineyard soils with the aim of killing soil-borne vine pests or vine diseases. It is usually carried out before planting. The earliest example of viticultural fumigation was the use of carbon bisulfide in France to combat phylloxera in the 1880s. Approximately 68,000 ha/167,960 acres were treated, requiring the painstaking insertion of about 30,000 holes per ha (12,000 per acre). Phylloxera is now controlled by grafting, and today fumigation is used primarily to control the nematode vector Xiphenema index of the virus disease fanleaf degeneration, but also for armillaria root rot, crown gall, and occasionally squirrels and gophers.