Table 1.

Source and quantity of N input into each of the three system comparisons via cover crops and fertilizer applications.

System	Comparison	Cover crop species	Cover crop N (kg N ha−1)	Fertilizer N (kg N ha−1)	Total N input (kg N ha−1)
Unfertilized organic	Cover crop species	Wheat	27	0	27
		Hairy vetch	78	0	78
		Bi-culture	100	0	100
Fertilized organic	Fertilizer vs. Fertilizer+N-Credit	Hairy vetch	78	0	78
		Hairy vetch	74	168	242
		Hairy vetch	74 + 102	56	232
Fertilized conventional	Urea vs. Organic fertilizer	Wheat	70	0	70
		Wheat	70	168	238
		Wheat	70	168	238