Scouting Area Fields

This year, drier conditions have brought about a number of issues.  Rootless corn syndrome continues to be an issue.  However, in areas that received rainfall, many of the plants will root into the moist soil and recover.  Those plants that have wilted and lay over, will not recover.

 

Dry soils also caused early season nitrogen deficiency on many corn fields.  Soil moisture is needed so plants can take up nitrogen.  Corn plants with nitrogen deficiency will have light green color.

 

Insect pests being found in other areas of the state should also be scouted.  False cinch bugs can cause damage to emerging soybeans when numbers get large.  They are often found following herbicide control of Peppergrass and Shepherds Purse.

 

Brown stink bug damage has been found on corn.  The damage occurred early and the plants exhibit twisted and damaged tissue.  Brown stinkbug is generally found along the field borders however, can be found across the field.

 

Musk thistle head weevil is working on local musk thistles.  The weevils eat the seed of the bloom causing the seed to be sterile. The underside of the head will have eggs and will look like drops of mud.  If you split heads open, there will be feeding larvae.

 

If conditions continue to be dry, there is an increased risk of spider mites.  Spider mites would preferably feed on soybeans but also can feed on corn.  They are often found on the underside of leaves.  Use a white piece of paper and shake the leaf so they will spill onto the paper.  They will move when exposed to sunlight and also a hand lens is helpful in diagnosis.

 

For more information, contact Wayne Flanary at 660-446-3724 or Heather Benedict at 660-425-6434, Regional Agronomists, University of Missouri Extension.