There have been a number of calls from folks who were disappointed in dicamba + glyphosate control on horseweed (marestail). Most of the applications were applied right before this wet cold period which is probably at least part of the reason for the poor control. A follow up application of either paraquat (Gramoxone Inteon) plus metribuzin in soybean or Cotoran or Caparol in cotton should finish off these survivors.  Other options would be Verdict plus glyphosate.  Ignite alone would also be a good choice when the temperatures warm up late next week.

Other folks have had success burning down the winter annuals but the residual has given out and now they have a flush of summer annuals.  Take a close look at these emerging summer annuals particularly if they are Palmer amaranth.  I have walked some fields where the Palmer amaranth is already 4” tall.  The most consistent option on Palmer that is this tall is paraquat (Gramoxone Inteon) at 40 oz/A.  If Palmer gets up to 6” or more then go to 48 oz/A of Gramoxone Inteon.  

There have been a lot of questions on what to do with fields that have not been burndowned yet with folks sitting on go to plant them.  Some of these fields now have well established horseweed present.  If the fields are to go to cotton then Ignite plus Cotoran or Caparol would be a good choice.  If the field is going to be planted to soybean then Ignite plus metribuzin should do a good job controlling the horseweed and many other winter annuals. Another option would be Verdict plus glyphosate plus 16 oz/A of 2,4-D.  Please note if you utilize this last option then you must wait 7 days to plant soybeans.