Echeverri Zuluaga, José JuliánRestrepo Betancur, Luis FernandoParra Suescún, Jaime Eduardo2012-04-122012-04-1220101794-4449http://hdl.handle.net/10567/156Introduction. Green forage production and its quality are some of the factors that determine the efficiency in the production and composition levels of milk in Antioquian intensive systems. Most common grass species is Kikuyo pennisetum Clandestinum, which can be found in 85% of specialized systems. This grass requires high chemical fertilization levels to achieve biomass productions enough to maintain the high loads they are submitted to by producers. Nitrogen fertilization, recommended for this kind of exploitations, moves between 50 and 70 Kg of nitrogen per hectare/grazing, and this means at least 400 Kg of nitrogen per year. The cost of fertilizers has obligated producers to look for strategies to reduce costs, using, among other options, organic matter as their compost source. Organic matter is important because of its impact on the soil’s structure and on some physical-chemical characteristics that help to a better use of the chemical fertilizer and finally increase the quality and the production of green forage. Objective. To determine the effect of the partial substitution of chemical fertilizers on the production of green forage and the leaf-stem relation in a farm located at the North of Antioquia. Materials and Methods. An experimental design in blocks randomized with three treatments was used, using as blocks 17 land plots in which the research was made. A minimum of three repetitions was made in every plot. The treatments were: 1) 50Kg of N/ha; 2) 25 Kg of N/ha plus 200Kg of organic fertilizar and 3) 25 Kg of N/ha plus 300Kg of organic fertilizer. Results. The statistic analysis was made by the use of the SAS GLM 9.0 version procedure. Conclusion. According to the analysis, there was no significant difference (p<0.05) between treatments for any of the evaluated characteristics, forage production per hectare and leaf:stem relation. This means that, under production and agronomic quality terms of the forage, the organic fertilizer replaced the chemical one, becoming a feasible alternative for fertilization in this kind of exploitations.esFertilizaciónCorporación Universitaria LasallistaKikuyo (Pennisetum Clandestinum)Pastos - Abonos y fertilizantesPastos - ProducciónPastos - CultivoForraje verdeFertilizantes orgánicosAbono orgánicoArticle