I received a question yesterday that seemed worth sharing with everyone…“What is a good threshold of aphid on wheat?”
According to the MU Pest Recommendations, the question isn’t that easy to answer because it depends on the type of aphid present.
Greenbughas a light green body with a darker green stripe on its back. ThGreenbugs are light green with a darker green stripe on its back.e threshold for greenbugs is 25-50 or more aphids present per linear foot of row in the fall. In the spring, they rarely warrant an insecticide application. They do not overwinter in Missouri and have to migrate here in the spring and that is why they are rarely a problem in the spring.
Bird cherry-oat aphids are a light green with an orange to red butt. The recommendation for it is 12-25 bird cherry-oat aphids or more per linear foot of row in fall through heading. They overwinter in Missouri and can build populations quickly in the spring, unlike greenbugs.
English grain aphids are light green with black “tail-pipes”, black antenna, and black knees. Treatment is recommended for these when 100 or more of them are present per tiller.