Improving barley yield on an acidic Boralf with crop rotation, lime, and zero tillage

Alternatives to the traditional small grain-bare fallow system on the Canadian Prairies are needed to avoid long-term deterioration of soil quality and to stabilize income. Canola (Brassica campestris L.) or pea (Piscum sativum L.) replaced traditional bare fallow in a 3-year rotation with barley (Hordeum vulgare L.) on a Mollic Cryoboralf near Beaverlodge, Alberta. Liming (none and 7.5 Mg ha(-1) in 1991) and tillage [conventional shallow (CT) and zero tillage (ZT)] were factorially arranged with crop rotation to assess barley grain and stover production during 1993-1995. Barley grain yield was 11+/-5% greater during the first phase following canola or pea than during the second phase, During both phases in the rotation, barley yield was 8+/-5% greater with pea than with canola. Crop rotation had little effect on barley stover production. Liming increased barley grain yield 17+/-8% and stover yield 13+/-13%, which could be attributed to the maintenance of soil pH at 6.2+/-0.1 after liming compared with 5.0+/-0.1 without liming. Zero tillage produced a grain yield advantage and a stover yield disadvantage in one of three years, but had no detrimental effect on stover or grain yield in other years. Volumetric soil water content of the surface 0-0.2 m under ZT was 0.03+/-0.02 m(3) m(-3) greater than under CT. Highest grain production (barley-barley-pea, limed, ZT) was 4.35+/-0.34 Mg ha(-1), while lowest grain production (barley-barley-canola, unlimed, CT) was 2.88+/-0.53 Mg ha(-1). Our results indicate that increased barley productivity could be achieved with pea compared with canola in rotation. Liming and ZT further improved barley yield on this acidic soil in the cold semiarid region of the Canadian Prairies. (C) 1999 Elsevier Science B.V. All rights reserved.