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Answer: Seed-placed fertilizer. The treatments compare seed-placed mono-ammonium phosphate (MAP) and seed-placed ammonium sulphate (AS) at low and high rates. The control (row 1 from the left) has no seed placed fertilizer. Row 2 has a low rate of MAP. Row 3 has a high rate of MAP. Row 4 has a low rate of AS. Row 5 has a high rate of AS. Row 6 (farthest to the right) has a blend of the two fertilizers. The research shows that at rates typically applied, AS is often more toxic than MAP. Not only does AS have a higher salt index, but ammonia is released in calcareous soils which can reduce plant populations below the optimum range. Seedrow application of AS to soils with a high CaCO₃ content, such as eroded hilltops, increases the risk of ammonia toxicity and can severely reduce plant stands. These conclusions are from research by University of Manitoba grad student Laryssa Grenkow, who presented at CanoLAB 2013 in Brandon.