Wheatgrass is a perennial forage grass adapted to low fertility alkaline soils in the Flooding pampa. It has an annual forage growth cycle characterised by a high spring-summer concentration and low values in winter. The objective of this study was to assess that it is possible to anticipate and increase forage growth and DM production of wheatgrass pastures applying nitrogen fertilization. The experiment was carried out at the Balcarce Experimental Station from 28/08/95 to 04/12/95. Using a completely randomized block design the effects of 6 levels of N: 0, 50, 100, 150, 200 and 250 kg Nha-1, added as NO3 NH4 were evaluated. The highest forage accumulation was reached with N250 with no differences (p\u3e0,05) with N200 and N150, showing a threefold increase in forage accumulation when compared with N0. A decreasing increment in forage accumulation was obtained with increasing N doses and the highest was with N50 and the lowest with N250 (43 kg DM and 17 kg DM/kg N applied respectively). The results show that nitrogen fertilization can increase and anticipate forage growth and DM production of wheatgrass pastures in late winter and early spring
