The Challenge of Weed Resistance
When I look back at the 2012 growing season, there are many challenges that we have not had to deal with in most recent years. An emerging challenge is the increasing weed resistance problem. I noticed many fields in central ND (Hwy 1 to Hwy 281) with large Kochia plants still remaining in the soybean fields in late August. Dr. Jeff Stachler from NDSU has been collecting samples and testing weed seeds from around the region and has updated his resistance map shown here.
There are now weeds suspected to be resistant to Glyphosate, Dicamba, 2,4-D & Starane. We need to be more proactive on our management with weeds. Rotating chemistries, using different herbicide resistant crops (LL Soybeans), incorporating PRE-emerge chemicals into our program, and using companion herbicides with our POST programs are all measures we can use to help in the prevention and control of these resistant weeds.
The black icons on the map are confirmed resistance weeds and the blue icons are highly suspected and being confirmed in the greenhouse. The three key weeds to be on the lookout for this next summer are Kochia, Waterhemp, and Ragweed. We do have new herbicide resistant crops coming down the pipeline (Enlist soybeans, Dicamba soybeans, HPPD resistant soybeans) but not a one of these will be the silver bullet in weed management so by being proactive now you can save yourself many headaches in the future.
