Both products are helpful tools for diamondback moth larval control. In cole crops, cabbage maggot activity has been observed in many areas. Recent rainfalls and cool temperatures are ideal conditions for cabbage maggot egg and larval survival. Flea beetle activity continues to be brisk this week in New York, Ohio, Illinois and Ontario. The threshold for flea beetles is 1 flea beetle per plant up to the 6th true leaf stage.
Radishes have a lower tolerance however if the tops are also being sold.
Growers will also notice imported cabbageworm butterflies moving about in fields. On early transplants, growers should also monitor carefully for the presence of Rhizoctonia disease which causes 'wirestem' symptoms and damping-off. These leafhoppers vector the aster yellows disease. Areas in Kent county and along the Lake Erie north shore are at highest risk from migrating aster leafhoppers. Carrot weevils are moving from their overwintering sites to newly planted carrot fields.