One of the authors developed a new type of seed-pellets, "macro-pellets" with are almond-sized matrix fertilizers with the legume seeds stuck on the surface by an adhesive. The effect of the macro-pellets on the establishment of introduced legumes was examined in a native savanna and in an improved pasture dominated by Brachiaria humidicola in the Llanos Orientales of Colombia. The macro-pellets were placed at a very low density in both pastures, with different methods of land preparation.
The use of the macro-pellets resulted in a satisfactory early establishment of legume seedlings, regardless of the differences in land preparation in both pastures. Although Centrosema brasilianum, grew vigorously after early establishment, it was selectively consumed by the grazing animals, so that the coverage was markedly reduced during the dry season. Desmodium ovalifolium, which was slightly less palatable during the rainy season, gradually invaded the pasture dominated by B.humidicola, and covered more than 60% of the whole area under minimum tillage 16 months after planting. Under the macro-pellet system adopted in the experiment, even a very low application rate of chemical fertilizer was effective enough to secure the growth of legumes.