Aphids, particularly the bird cherry oat aphid, are abundant in many fields. Scouting this past week indicates that fields that are heading to flowering have had the larger populations of aphids when compared to younger fields. The bird cherry oat aphid prefers to feed on foliage, so parting the canopy reveals their presence lower in the plants.

With the large numbers of armyworm moths active, there is still the need to monitor for armyworm larvae in small grain fields. Sweep net sampling in grassy field borders was finding 1/2 inch size larvae late last week. Larvae in fields are likely to be smaller. Sweep net sampling is NOT the ideal way to monitor this pest. It really requires parting of the canopy and searching for signs of feeding or perhaps larvae hiding at the base of plants. Sweep nets might be useful late in the day, near dusk, or if cloudy conditions are present.

Another heads up for larvae, though not in small grains. Along with the large flight of armyworm moths, there were also large numbers of Variegated cutworm moths. This pest migrates into the region and produces multiple generations, depending on when they arrive and the length of the season. In the past, variegated cutworms have caused most of their problems in sugar beets. They also tend to be a problem for homeowners in their garden areas. So keep a close eye on beets for signs of cutworm feeding in July and August, a time when most people aren’t scouting for this problem.

Phillip Glogoza
Regional Extension Educator - Crops