Corn is popping out of the ground throughout the bootheel. We hope your corn is problem free and safe from blackbirds. The cold, wet weather we have had lately can create ideal conditions for plant diseases and herbicide applications that are put out windy weather can become drift problems. Jason and I saw this corn last week that was having trouble. The problem here isn’t a plant disease or herbicide drift – the problem here is the field saw too much Fomesafen last year.
Fomesafen (Reflex® (http://www.cdms.net/LDat/ld6BJ013.pdf) and Flexstar® (http://www.cdms.net/LDat/ld6BM020.pdf)) is a PPG oxidase inhibitor herbicide which ultimately results in leaky cell membranes and death in susceptable plant species. This herbicide was used extensively in the Bootheel because it works well on pigweeds and Reflex® currently has a Missouri 24C label for use as an early preplant in cotton (http://www.cdms.net/LDat/ld6BJ038.pdf) for this reason. We had some problems last year controlling pigweeds in several crops (http://ppp.missouri.edu/newsletters/ipcm/archives/v19n16/a1.pdf).
The Missouri Pest Management Guidelines (get your own free copy at: http://extension.missouri.edu/publications/DisplayPub.aspx?P=M171) and the label of the fomesafen formulation you choose will specify a maximum yearly rate for the region within which the herbicide is used. Overapplication can harm the next crop and violates the label. The use of brand names does imply endorsement and is merely to facilate recognition of the herbicide.