Although tillage systems and crop rotations can affect crop production and uptake of nutrients, their long-term effects, particularly their interactions, are not well-documented. Therefore, we measured the N, P, and K contents and yields of crops through two rotation cycles, especially wheat (Triticum aestivum L.), of four crop rotations managed under conventional tillage (CT) and no-tillage (NT) systems. The study was conducted 1993 through 2000 on a sandy loam soil in northwestern Alberta, Canada. The four-course crop rotations were: (i) field pea (Pisum sativum L.)-wheat-canola (Brassica rapa L.)-wheat; (ii) red clover (Trifolium pratense L.) green manure-wheat-canola-wheat; (iii) fallow-wheat-canola-wheat, and (iv) continuous wheat (CW). The crops were fertilized using regional recommendations based on soil test results. Previous crop effect on wheat yield was in the order: field pea = red clover green manure > fallow > canola > wheat (CW); it had little influence on N, P or K content in wheat grain or straw. There was no interaction of tillage with crop rotation on wheat production or nutrient content. Tillage treatments affected neither production of other rotation crops nor their nutrient concentrations. During the second rotation cycle, N fertilizer requirement decreased, and wheat yield was 22% higher, under NT as compared to CT. This study showed that (i) field pea is an attractive replacement for red clover green manure; and (ii) recommendations for N from soil test results should factor in the type of tillage system used. Key words: Canola, field pea, red clover, nitrogen, tillage, wheat