The production and utilization of complementary cereal/legume bi-crops as ruminant feeds is beneficial for several reasons. The nitrogen fixation by the legume reduces the amount of fertilizer nitrogen required by the cereal. The cereal in turn supports the legume, thereby preventing the lodging that typifies pure stands of mature forage peas. When bi-crops are fed, the legume and cereal components respectively provide relatively low cost protein and energy, which may be synchronously supplied to the animal. In Denmark, pea-barley bi-crops are reported to reduce the cost of feeding without reducing intake and animal performance (Kristensen, 1992). However, little is known about the intake potential and level of animal performance sustainable from such bi-crops when produced and fed under UK conditions. Therefore this study determined the intake, in vivo digestibility and nitrogen (N) balance in sheep of spring sown, peawheat bi-crop silages harvested at three stages of maturity.