“These pigweed are kicking our #&^”….. That quote one county agent said to me the other day fully defines the weed issues in many soybean and cotton fields.  A number of soybean fields that did not have a Pre applied herbicide have become partially or completely over run with Palmer amaranth (Picture left) last week.  Some of these fields will be destroyed this week and replanted with a Pre applied herbicide this time.  Others where large patches of Palmer are the issue will be either partially destroyed and replanted or sprayed several more times with a PPO herbicide.  Neither option is a good one. Part of the problem has been the good wheat crop.  By the time the wheat was harvested and doubled cropped, the Palmer in the earlier soybean fields planted in May had become too large for fomesafen (Flexstar, Reflex, Prefix, Rhythm, Dawn, etc.) to control. Other issues have been folks who thought they could get by one more year without glyphosate-resistant (GR) Palmer showing up in their fields.  After they sprayed glyphosate 2 weeks ago, they found out glyphosate was no longer effective on their Palmer.  The Palmer had become 6” tall and too large to be effectively controlled with fomesafen. Finally, some of the Palmer in a few fields was sprayed timelier (3 to 4”) with a fomesafen product and got considerable grow back.  I am really not sure what is going on there, but we are looking into it.

All the issues in mid-June bring to mind the fact that many of the pre applied herbicides applied in late-May/early-June will begin to play out this week.  They have started to do so in our tests.  Everyone should be monitoring soybean fields for newly emerged Palmer amaranth and be ready to have them sprayed timely!