EN
A field study was conducted in 2006–2008 at the Czesławice Experimental Farm belonging to the University of Life Sciences in Lublin. Its aim was to determine the size and structure of spring wheat yield, as well as weed biomass in a spring wheat crop under the conditions of herbicide application and crop protection using the „Aktywator” weeder harrow, with harrowing done at two different time of the day (daytime or nighttime). It was proved that harrowing done at the 3–4-leaf stage of spring wheat promoted the formation of similar grain yield and resulted in similar weed infestation of the spring wheat crop as compared the object with chemical weed control using a mixture of the herbicides Apyros 75 WG and Starane Super 101 SE. The yield-increasing effect of harrowing was not dependent on the time of performed treatment. However, harrowing at night produced better effects for the reduction of weed biomass than harrowing during the daytime.