This project is part of a collaborative effort among researchers, government, commodity groups and the livestock industry to develop best management practices for utilization of liquid hog manure to improve forage production, cattle production and environmental quality. Our contribution to the project is to quantify the major greenhouse gases (GHG) nitrous oxide (N₂O) and methane (CH₄) emitted from soil, as well as from cattle dung and urine patches affected by steers grazing manured or non-manured forage. The study site is located in Southeast Manitoba on 98 acres of land, 8 miles south of the town of La Broquerie, Manitoba. Treatments were no manure (control); 110 lbs of available N applied in the spring (full); and 110 lbs applied half in spring and half in fall (split). The project began in the fall of 2003. Generally, CH₄ emissions from soil increased shortly after manure addition to plots with N₂O emissions lagging until the soil dried. After fall manure application to the split plots in 2004, relatively little CH₄ and N₂O fluxes were measured, compared to those following spring application. Methane and nitrous oxide fluxes following manure application were dependent upon the spatial pattern of soil moisture across plots; high soil moisture promoted CH₄ and lower soil moisture N₂O emissions from manured soil. Dung patches from steers grazing manured forage initially (1-3 days) produced more CH₄ than that from steers grazing unmanured forage. As the dung patches matured greater N₂O was produced from dung of steers grazing manured than non-manured forage. Artificial urine was produced to mimic the higher concentration of nitrogen compounds in urine of steers grazing manured forage. Nitrous oxide emissions increased following the application of urine. Results of this study will be combined with cattle enteric CH₄ emission data in order to determine GHG emissions from each pasture treatment.