Legumes are generally lower yielding than cereals (Lauriault, unpublished data, 2001), but they fix atmospheric nitrogen in symbiosis with Rhizobial bacteria that improves soil fertility ( Dung et al., 2005 and Contreras-Govea et al., 2011b) and forage yield and quality for both legumes and non-legumes in mixed sowings ( Lauriault and Kirksey, 2004, Ayub et al., 2008 and Ibrahim et al., 2012)