Grape phylloxera is an aphid-like insect pest of grapevines. It exists in vineyards world-wide and was first discovered in Oregon vineyards in the early 1990's. It has more recently been found in the eastern reaches of Oregon and Washington's Walla Walla Valley and other areas of eastern Washington, an area thought to be free of this pest. Most of the vineyards in those regions are own-rooted Vitis vinifera cultivars that are highly susceptible to decline by grape phylloxera. This video presented by Washington State University Extension faculty Dr. Michelle Moyer and Gwen Hoheisel, provides good information and visuals on how to identify phylloxera in infested vineyards of eastern Washington. Keep in mind that there may be some slight differences for observing phylloxera in western regions of Oregon due to soil type and temperature differences. Also, phylloxera is not a concern in vineyards that are planted to resistant rootstocks, which are prevalent in much of western Oregon production regions.
For further information about grape phylloxera, see our OSU Extension Publication: