A trail on Brachipará (Tangola) grass was conducted in Santa Cruz, Guanacaste which is located 54 masl and has an annual rainfall precipitation of 1,834 mm. The production of green and dry phytomass, as well as grass growth and forage density, were evaluated for the Brachipara grass under three dosage levels of nitrogen fertilizer (0, 100 y 200 kg.ha<span name="style_sup">-1</span>.year<span name="style_sup">-1</span>) per year and three different harvest frequencies (30, 60 y 90 days). The production of dry phytomass increased with higher nitrogen doses: 2,997.90 kg with 0 kgN.ha<span name="style_sup">-1</span>, 4,708.33 kg with 100 kgN.ha<span name="style_sup">-1</span> and 6,583.33 kg MS.ha<span name="style_sup">-1</span> with 200 kgN.ha<span name="style_sup">-1</span> application. The Brachipará grass likewise exhibited a similar pattern in relation to forage density and nitrogen fertilizer applications. In this manner, the 0 kgN application yielded 26,88 kg MS.ha<span name="style_sup">-1</span>.cm<span name="style_sup">-1</span> where the 100 kg application yielded 32,93 kg MS.ha<span name="style_sup">-1</span>.cm<span name="style_sup">-1</span> and the 200 kg dosage produced 45,87 kg MS.ha<span name="style_sup">-1</span>.cm<span name="style_sup">-1</span>. Furthermore, the performance of dry phytomass per hectare was affected by age, reporting values of 2227,08 kg at 20 days, 5031,25 at 40 days and 7031,25 kg at 60 days of age respectively. Multiple equations were calculated for some of the variables under evaluation and it was concluded that for Brachipará grass, it is recommendable to apply 200 kg N.ha<span name="style_sup">-1</span>.year<span name="style_sup">-1</span>
B.arrecta; B. mutica; Brachipara grass; phytomass; nitrogen; harvest frequencies