Spread of barnyard grass, growing in southern Sweden has accelerated during the last decade and is rapidly moving northwards. No herbicide-resistant populations have been reported from Sweden thus far, but it is only a matter of time before barnyard grass will develop herbicide resistance in Sweden. We are currently lacking field trials with a focus on barnyardgrass. To evaluate the effects of preventive control methods in combination with different herbicide-use strategies, we plan to investigate effects of an integrated weed management (IWM) approach, to control barnyard grass by means of field trials in 3 regions of Sweden during 3 years. Such an approach, using combinations of preventive and direct weed control measures is necessary to reach the following goals: 1) to obtain control over the present populations of barnyard grass by means of IWM 2) to slow down/halt the development of herbicide resistance in barnyard grass and 3) to prevent an extension of the population northwards.