Despite the discovery near Kennewick in 1894 of the destructive grapevine root pest phylloxera, the vast majority of Washington State’s vineyards continue to be planted to wine and juice grapes grown on their own roots. While juice grapes are relatively tolerant of the insect, European wine grapes can succumb within a few years of infestation of their roots. The only long-term solution to this threat is grafting to rootstocks derived from North American grapevine species that have coevolved with the insect and have thus learned to tolerate or resist attack. Luckily, but for reasons that are not entirely clear, phylloxera […]