Many confectionary sunflower fields are above the economic threshold of 1 weevil per head. When sampling, choose four different sites within 75 feet of the edge of the field. Count the number of weevil for three plants per sites for a total of 12 plants sampled. Later seeded sunflower fields will probably escape the heavier pressures since the weevils are concentrating in the earlier seeded sunflower fields. The reason for treating at an earlier plant growth stage is because adverse weather conditions or busy aerial applicators may delay the actual application.
Timing is very critical for successful control of red sunflower seed weevil.
If spraying is done too early, weevils can reinfest a field requiring a second treatment. The new generation of the crucifer flea beetles is emerging now. Most canola fields are blooming to pod development and these beetles should not represent a problem to the crop. Certain areas, like McLean and Ward Counties, are reporting extremely high populations. Flea beetles are feeding on the green tissue of the upper seed pods which can cause small seeds and shattering during harvest.