Small Grain Aphids Have Arrived, but at Extremely Low Numbers

I scouted our winter wheat planting date by barley yellow dwarf virus trial this morning at Lancaster WI. Our earliest planting date (September 17th 2008) survived the winter very well and is nearing the Zadoks 30 (pseudostem erection) growth stage. Crop development of the later planting dates (September 30th and October 13th) are significantly behind the earliest date, Zadoks 13, 22 and 12, respectively. Across all of our plots I found only one Oat Bird Cherry aphid. The established spring threshold for this pest is 50 aphids per linear foot of row.

Oat Bird Cherry Aphid
Drawing Courtesey of Dennis Murphy