Authors: P. Milburn, J.A. Macleod and B. Sanderson
Download file: https://library.csbe-scgab.ca/docs/journal/39/39_4_263_ocr.pdf
Published in: CBE Journal » CBE Journal Volume 39 (1997)
The ability of a catch crop (winter wheat) and a lightly incorporated straw mulch to reduce N03-N leaching following harvest of early potatoes (variety Superior) on Prince Edward Island (PEl) was evaluated over two cycles of a potato-cereal rotation, from spring 1989 to spring 1993. The extent of nitrate leaching from each treatment was indicated by the mean annual (spring to spring) flow-weighted N03-N concentration (N03-Nr) of tile drainage water. Mean annual values for the winter wheat and barley crops in the rotation ranged from 2.9 to 7.7 mg/L. For the first potato crop, both fall treatments significantly reduced N03-Nr values, from 12.8 mg/L in the control to 10.7 mg/L for the straw incorporated and to 8.8 mg/L for the winter wheat crop. For the second potato crop, only the straw-incorporated treatment was significantly lower than the control, 27.5 compared to 18.0 mg/L. The relatively short time available for plant biomass accumulation following fall planting in PEl appears to limit the ability of winter wheat to consistently reduce post-harvest N03-N leaching. Soil profile N03-N content measured by coring in late fall and early spring after potatoes were grown did not show any significant differences among treatments.