The foliar form of Grape Phylloxera (GP) is quite common throughout Minnesota and most eastern grape growing regions of the U.S. Although we have experienced a late spring so far this year, the first grape leaves for most hybrids have started to appear; this is a good time to begin monitoring for the “yellow crawler” stage of GP, as the crawlers hatch from their “mother” galls (including a female with several eggs, Fig. 1).