The blade roller offers new opportunities to reduce tillage, especially in organic farming. The objective of the study was to reduce tillage in the green manure phase of a green manure-wheat ( Triticum aestivum L.) rotation by substituting tillage with blade rolling. A pea ( Pisum sativum L.) and oat ( Avena sativa L.) green manure was used for two site-years at Carman, MB, while a pea monocrop was used for one site-year at Oxbow, SK. At pea flowering, the green manure was terminated by rolling, tilling, or a combination of the two. Ammonia emissions were greater in the no-till compared with the tilled green manure system, though total ammonia losses were low (<13 kg ha -1). Replacing tillage with rolling reduced soil nitrate N in autumn after green manure by 56 to 88 kg ha -1 in the 0- to 60-cm soil depth. Reduced green manure tillage did not affect wheat establishment but delayed plant development in some instances. Fewer weeds were often observed in wheat in the no-till compared with tilled plots. Total N supply in the green manure-wheat system was reduced in the no-till system compared to the tilled only system at two out of three site-years by an average of 44%. While reduced N supply in the reduced tillage system coincided with reduced wheat yield and protein, it was concluded that factors other than N also were involved. Using the blade roller instead of tillage in the green manure year provides soil conservation benefits and facilitates wheat production the following year.
