Details for Fertilizer, Soil, Nutrients

I can't answer what the best product for pulse crops in Saskatchewan is but I can help you through the differences in the products you've listed. 40 Rock has an analysis of 12-40-0-6.5-1, all 6.5% of the sulfur is in the form of sulfate sulfur so it is immediately available. MicroEssentials SZ, or MESZ, has an analysis of 12-40-0-10-1, 5% of the sulfur is in the sulfate form and the other 5% is in the elemental form, which will need to convert to sulfate sulfur to be available. MAP+MST has an analysis of 9-43-0-16, 15% of the sulfur is in the elemental form. 40 Rock and MESZ are very similar, biggest difference being 40 Rock has 1.5% more sulfate sulfur and no elemental, MESZ having 1.5% less sulfate sulfur but 5% elemental. MAP+MST does not have zinc like 40 Rock or MESZ. 40 Rock and MAP (11-52-0) are not the same product, 40 Rock having 12% less phosphorus and the addition of sulfur and zinc within the granular. In regards to salt index, all these products would be considered low salt with salt indexes ranging from 22-27. To answer what the best product for pulse crops would depend on what exact pulse crop is grown and it's needs for P,S, and ZN along with the field needs of those nutrients.

MEZ is good with a pretty low salt index.