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Agricultural producers across Canada and the United States consider foxtail barley (Hordeum jubatum L.) and downy brome (Bromus tectorum L.) major weeds that are detrimental to both field crop and livestock production. Study objective was to evaluate the ability of potential pure and mix forage treatments to suppress foxtail barley and downy brome on two different salinity ranges. Two Alberta Canada sites were selected: Site1 was slightly to moderately saline (2 to 8 dS/m ECe) and Site2 was slightly to severely saline (2 to 16 dS/m ECe). Ten forage treatments were compared to unseeded control and were: Saltmaster mixture (20% each of tall fescue, tall wheatgrass, slender wheatgrass, smooth bromegrass and alfalfa), AC-Rocket smooth bromegrass, Spredor 4 alfalfa, AC-Saltlander green wheatgrass seeded at 15 or 30 cm row spacing, Nuttall's salt-meadow grass, Polar northern wheatgrass, Green wheatgrass/slender wheatgrass mixture, Poole western wheatgrass and Orbit tall wheatgrass. Each site was evaluated for salinity, pre-seed treated with glyphosate, cultivated and harrow-packed and most forage treatments were seeded at 30 cm row spacing. Site1 and 2 were seeded May 16 and June 29, 2006, respectively. After three growing seasons at site1, AC-Saltlander green wheatgrass 15 and 30 cm, green wheatgrass/slender wheatgrass mixture, smooth bromegrass and tall wheatgrass reduced average foxtail barley and downy brome populations to less than 5% and 4% of the total biomass (P<0.0001), respectively. At Site 2, five growing seasons were needed and only AC-Saltlander green wheatgrass 15 and 30 cm and the green wheatgrass/slender wheatgrass mixture lowered foxtail barley plant populations significantly (P<0.0001). These reductions were to 8%, 8% and 19% of the total biomass, respectively.  Downy brome was not present at this site. Results show that as the salinity increases, forage options become more limited, and green wheatgrass becomes the best choice to compete with foxtail barley and downy brome.