This means that mites will be present when winter wheat is seeded. It is important to control volunteer wheat in fallow strips and to delay winter wheat planting. The delay in the spring wheat crop will also be a factor in wheat streak mosaic problems in 1996. If you have experienced wheat streak mosaic virus disease in the 1993 and 1994 growing years, it is even more important to break this potential green bridge. Control of EGA is not suggested unless infestation reaches 50 aphids per stem in boot to heading stage.
Wingless forms have a tail just above the pointed abdomen, giving it a two-tailed appearance.
RWA cause very characteristic leaf damage, including tightly rolled leaves with dramatic white striping. Treatments for RWA are recommended when 15 percent of the tillers are infested when flowering begins, or if 25 percent of tillers are infested at early milk stage. After soft dough stage, insecticide treatments are of little benefit. Both of these aphid species can survive the summer on a number of grass host plants, and we may see them moving into our winter wheat this fall. Winter wheat seedling plants infested at 2 leaf stage produced fewer tillers and were less winter hardy than plants infested at tillering.