Since 2003, Armillaria gallica (Marxm. and Romagn) infectionshave been observed in blueberry production systems in the Trentino region of northern Italy (Prodorutti et al., 2006b). Armillaria spp.-infected root residue from forest and/or fruit trees that remains in the soil may act as a source of disease inoculum for crops grown on that soil (Prodorutti et al., 2009). A. gallica has also been found in bark used as mulch in blueberry production systems,suggesting that infected bark may be a source of inoculum for Armillaria root rot in agricultural crops (Prodorutti et al., 2009).