Counties in dark gray contain at least one population of kochia with genetically confirmed resistance to Groups 2, 9, and 14 herbicides. Light gray counties are those that submitted samples, but did not have resistance to all three herbicide groups. (Photo source: Zack Bateson, Research Director, National Agricultural Genotyping Center)
Herbicide-resistant kochia remains one of the most troublesome weeds to manage in N.D. fields, according to Victor Gomes, North Dakota State University Extension cropping systems specialist. Its management has become increasingly difficult due to its high adaptability to adverse conditions, allowing kochia to outcompete crops under stressful conditions, and its resistance to multiple herbicide gro…