Walley, F.L.Pennock, D.J.Hnatowich, G.L.Solohub, M.2018-09-062018-09-061999-02-25http://hdl.handle.net/10388/10052A broad association between landform and distinctive pedological regimes, as influenced by the hydrological pattern of the hillslope is known to exist in glacial till landscapes of Saskatchewan, Canada. We used image analysis of aerial photographs to delineate different pedological regimes within a typical glacial till field in the thin Black soil zone. Three distinctive areas (upper, mid, and lower slope) were identified as “management units”. Variable rate N and P fertility trials using wheat and canola as the test crops were initiated in 1996 and conducted over a three-year period. The data associated with the N treatments are discussed in this paper. Results indicated that the management units developed on the basis of the aerial photographs were agronomically meaningful. In particular, mean yields on upper slope positions were consistently less than yields achieved on upper slope positions. Moreover, N fertilizer application did not mitigate the impact of slope position on yield and it was concluded that moisture limitations on upper slope positions limited the extent to which wheat and canola responded to fertilizer application. On the basis of the results from this study, it was concluded that a meaningful variable rate program could be developed for canola whereas variable wheat yield responses and low financial returns limited the success of the variable rate fertilizer program for wheat.enAttribution-NonCommercial-NoDerivs 2.5 CanadaPresentation