Livestock manure improves acid soil productivity under a cold northern Alberta climate

The acidameliorating properties of feedlot cattle manure on barley and canola productivity in acid soils were evaluated from 2003 to 2007 at Fort Vermilion and Beaverlodge research stations in northern Alberta, Canada. Treatments included Control, NPfertilizer, Lime+NPfertilizer and manure at 80 (M80) and 160 (M160) Mg ha-1. Manure and lime were applied once in 2003 and NPfertilizer was applied annually. Manure significantly increased soil pH from around 4 to>5 and this increase persisted over the 4-yr period. At Fort Vermilion, M160 reduced soil 0.01 M CaCl2 extractable Al and Mn contents from 2.9 and 11.7 mg kg-1 (Control) to 1.1 and 8.9 mg kg-1 and barley straw Mn content from 313 (Control) to 220 mg kg -1. Soil P(Mehlich 3) and K (0.01 M CaCl2 extractable) contents in M160 were more than two times those in the Control, while values from fertilizer treatments were not different from the Control. Crop grain N, Pand K uptakes and yields in M160 were twice those of the Control. In northern Alberta, manure application to acid soils at a rate of 160 Mg ha-1 once every 4 yr had the same effectiveness as Lime+NPfertilizer in increasing soil pH and improving soil fertility and crop productivity at the field scale.