The research was conducted in the Arrayanes farm, Catambuco village, Department of Narino, Colombia. The objective was to evaluate the soil relationship on the composition of Loliumhybridum grass in monoculture and the mixture of Dactylisglomerata, Holcuslanatus and Loliumsp grass. The monoculture soil indicators in upper, middle and lower areas showed differences (P 0.05) were observed when the analysis per period (wet-dry) was performed. In pasture in mixtures, the results were statistically different (P 0.05). The results for grass mixture, by area showed no differences (P>0.05) in RD and TP. The AD values for time and zone in monoculture and mixed pastures were 0.66 to 0.71 (g/cc), RD 2.06 to 2.32 (g/cc) and TP between 66 to 70.9%. In monoculture differences (P<0.05) were observed, in the recovery period (RP) and biomass production (BP), both by time and by area. However in grass mixture, the RP was different (P<0.05) between periods, but no differences were observed by area.The RP values by period and area ranged from 26 to 32 d, the BP went from 4.4 to 4.8 (kg/m) in monoculture, while in the mixed prairie RP ranged from 45 to 60 d and BP from 4.9 to 5.8 (kg/m). In the bromatological analysis differences were observed (P<0,05) only per region for the crude protein (CP), neutrall detergent fiber (NDF), acid detergent fiber (ADF), calcium (Ca), phosphorous (P) , magnesium (Mg), and total digestible nutrients (TDN) were observed both in the prairie in monoculture and in the mixture. The values obtained were: PC 25,2%; FDN 50,6%; FDA 25,1%; NDT 64,6% and 0,22%, 0,30%, 0,14% for Ca, P and Mg, Veterinaria y Zootecnia ISSN 2011-5415 Vol 8 No.1, enero junio de 2014 ©Universidad de Caldas 67