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Growing winter cereal grain/forage legume intercrops can provide multiple benefits to cropping systems in the North Central USA. Intercropping red clover (Trifolium pratense L.) with winter cereal grains can provide forage and a green manure crop. Seeding rate recommendations for sole crops may not optimize intercrop system productivity if interactions exist. This study was conducted during the 2002-2003 and 2003-2004 growing seasons to determine optimum cereal grain and red clover forage seeding rates for maximum returns using partial budget analyses. In March, red clover was frost-seeded at 0, 300, 600, 900, 1200, and 1500 seeds m-2 into winter wheat (Triticum aestivum L.) and triticale (X Triticosecale Wittmack) seeded at 100, 200, 300, and 400 seeds m-2 the previous October. Triticale and wheat maximized returns at seeding rates of 300 and 400 seeds m-2. No cereal grain by red clover seeding rate interactions were detected for red clover dry matter production (DM). Red clover plant densities after cereal grain harvest were 10 to 22% of the original seeding rates. Red clover DM production and return was maximized at 3.49 Mg ha-1 with 900 seeds m-2 in 2003 and 6.67 Mg ha-1 with 1200 seeds m-2 in 2004. Winter cereal/red clover intercrops in the North Central USA can maximize return using a cereal grain seeding rate between 300 and 400 seeds m-2 and red clover seeding rates between 900 and 1200 seeds m-2.