Late June

With the continuing droughty weather conditions, two insects demand attention in our fields.  First, are the two spotted spider mites which are greenish yellow with two black spots on their sides.  They have four pairs of legs.  Hot, dry weather will allow the spider mite population to grow rapidly.  However, cool temperatures and high humidity will allow naturally occurring fungus to generally control the spider mites.

The second insect is the Japanese beetle.  These beetles are iridescent copper and green with white hair tufts on their sides.  My concern is with their feeding on corn silks prior to pollination.  If the silks are exposed (showing) from the ear shoot, things are ok for pollination to occur.  Silks are generally fertilized 24 to 48 hours after they emerge if corn pollen is present.


                  Spider Mites (photo by ISA)                                          Japanese Beetle (photo by Iowa State Univ. Ext.)