To plan an experiment means to decide how to observe and measure in order to minimize randomized variations and stress the effects of the factors analyzed. Namely, it is of major importance to minimize experimental errors. Thus, the experimental design is expected to meet some of the principles stated in order to minimize experimental errors. Local control is one of the principles anticipated to be met by an experimental design. In addition to the variations tested, local control is expected to isolate the significant variations from the experimental error. The choice of the experimental design is one of the means of realization of local control. The objective of the study was to point to the possibility of increasing reliability of conclusions by changing experimental design. Namely, the Latin square along with some of its characteristics may be anticipated to solve some of the issues with regard to experimental design when agricultural production is concerned.