A field trial with four grass species was established in the year 1996 in Prague, The stands were one or three times per year cut with the mass removing or one or two times mulched The dry mass yields and the share of the sown species (by weight method) were measured from the third to the sixth year of vegetation. The highest share of the sown species with the slowliest decreasing during the years was at Arrhenatherum elatius (41-72% in the sixth year), Bromus catharticus extincted in the fifth year. The species choose had a higher importance for conserving of the original botanical composition than the way of harvest.