There have been a number of calls on corn that is showing some stunting and interveinal chlorosis (Picture right).  In some cases the injury is more substantial with some leaves showing some burn.  The reason for some of this injury is fomesafen (Flexstar, Prefix, Reflex, Dawn, Rhythm) carryover from last year. There have not been many calls yet, but I would expect more as folks evaluate their fields over the next week or so. The last time I can recall a significant number of fomesafen carryover reports was back in 1994.  That scenario was very similar to what we have this spring with an early planted corn crop (though not this early) following a soybean crop that was late planted the previous year.  Pigweed was the target then as well with a lot of Flexstar being applied in late June and July.  The fall in 1993 was fairly dry like the fall of 2011, which helps make the fomesafen more persistent.  All in all, this makes for a perfect set-up for seeing fomesafen carryover injury to our March planted corn this year.

Fortunately, most of the corn suffering from fomesafen carryover in 1994 shook it off after about 10 days and went on to make a good crop.  I would expect a similar outcome this spring to the corn that is showing the stunted/yellowing symptoms now.

Corn plants that have more pronounced injury where new leaves are wrapped up in dead leaf material will need to be assessed next week. If the new leaves appear to be growing through the old leaf material it is a keeper. If on the other hand the new leaf appears to be knotted up in dead leaf material it may not produce an ear. Those plants should be assesses as stand loss and stand evaluation taken to determine if replant is warranted.