Stewart, J.W.B.Moir, J.O.Tollefson, L.C.2018-09-262018-09-261980-02-18http://hdl.handle.net/10388/11121Data on yield and P uptake by flax and wheat is presented from the first year of an eight year residual phosphate (P) study located on the Kernen Farm of the University of Saskatchewan. Comparison of seed-placed (0, 5, 10, 20, and 40 kg P ha-1) and broadcast P (0, 40, 80, 160, and 320 kg P ha-1) treatments showed that there was a yield response to both types of P fertilizer application with maximum yields being obtained in wheat by either 40 kg P ha-1 seed-placed or by broadcast P application of 80 to 160 kg P ha-1, and in flax by 5-10 kg P ha-1 side-banded or 80 kg P ha-1 broadcast. Laboratory studies related the prediction of fertilizer P response from seed-placed treatments to broadcast treatments by use of P sorption and P extraction techniques. P sorption isotherms were run on over 300 soil samples taken from the 0-15 cm layer of cultivated fields representing the majority of the cultivated soil associations in Saskatchewan. This data would suggest that rates of P broadcast should be four to eight times higher than recommended seed-placed or side-banded rates in the same Soil Zone with the same available P content.enAttribution-NonCommercial-NoDerivs 2.5 CanadaResidual phosphate studiesPresentation