Found in fields, pastures, rangeland, waste places, fence rows, roadsides, and irrigation ditches. Russian knapweed is not grazed by livestock because of its bitter taste. Deer rarely eat it.
Russian knapweed can be an aggressive and difficult to control pest in alfalfa, clover, other forage crops, pastures, and occasionally in row crops. It has become more abundant in recent years. It is a noxious weed in many states.