2Jeranyama P, Hesterman O B, Sheaffer C C. Medic planting date effect on dry matter and nitrogen accumulation when clear-seeded or intercropped with corn[J]. Agronomy Journal, 1998,90 : 616-622.
3Simmons S R, Martin N P,Sheafer C C,et al. Companion crop forage establishment: Producer practices and perceptions[J]. Journal of Production Agriculture, 1992,5: 67-72.
4Agboola A A, Fayemi A A A. Fixation and excretion of nitrogen by tropical legumes[J]. Agronomy Journal, 1972,64 : 409-412.
5Robinson R G. Oat-pea or oat-vetch mixtures for forage or seed[J]. Agronomy Journal, 1960,52:546- 549.
6Walton P D. Annual forages seeding rates and mixtures for central Alberta [ J]. Canadian Journal of Plant Science, 1975,55 : 987-993.
7Droushiotis D N . Mixtures of annual legumes and small-grain cereals for forage production under low rainfall[J]. Journal of Production Agriculture, 1989, 113:249-253.
8Anil L J,Park R H, Phipps M F A. Temperate intercropping of cereals for forage: A review of the potential for growth and utilization with particular reference to the UK[J]. Grass Forage Science, 1998, 53:301-317.
9Hall M H , Kephart K D. Management of spring - planted pea and triticale mixtures for forage production[J]. Journal of Production Agriculture, 1991,4 : 213-218.
10Chapko L B, Brinkman M A, Albrecht K A. Oat, oat-pea, barley, and barley-pea for forage yield, forage quality,and alfalfa establishment[J]. Journal of Production Agriculture, 1991,4 :486-491.
