Are you seed-placing your phosphorus (P) and basing application rates on seed safety rather than crop requirements? You may be leaving yield on the table. Recent research out of the University of Manitoba examining seed-safe rates of P and sulfur (S) in canola is showing that P applied at rates based on seed safety may not be adequate to maximize canola yields.
Record yields equal record removal of nutrients and should indicate a need for record soil nutrient replenishment.
Monoammonium phosphate (MAP) and diammonium phosphate (DAP) are excellent sources of phosphorus (P) and nitrogen (N) for high-yield, high-quality crop production. Research trials at 42 field sites in seven Corn Belt states showed an average corn yield of 162 bushels per acre with MAP and 159 with DAP. MAP (11-52-0) and DAP (18-46-0) contain about 90 percent water-soluble P, which is well above the 60 percent needed for optimum crop growth.
In 2010, most farmers were anxiously awaiting long-promised drought-tolerant corn hybrids, Denny Friest, however, would have welcomed moisture-tolerant hybrids on his north-central Iowa farm. Too much moisture often poses the biggest challenge of farming the dense, poorly drained Clarion-Nicolette-Webster soils, which are typical of North America’s vast Prairie Pothole region.
Evaluate the yield response of spring wheat to MicroEssentials® S15® (13-33-0-15S) compared to MAP (11-52-0) + AS (21-0-0- 24S) and MAP.
Scientists from Arizona State University compared fluid ammonium polyphosphate (10-34-0) applied in irrigation water with granular monoammonium phosphate (MAP) broadcast and irrigated into the soil as phosphorous (P) sources for high-yield alfalfa (eight cuttings per year) and to study movement and availability of P in a calcareous soil.
Evaluate the yield response of spring wheat to MicroEssentials® SZ® (12-40-0-10S-1Zn) compared to MAP (11-52-0) + AS (21-0-0- 24S) and MAP.
Triple superphosphate (TSP) was one of the first high-analysis phosphorus (P) fertilizers that became widely used in the 20th century. Technically, it is known as calcium dihydrogen phosphate and as monocalcium phosphate, [Ca(H₂PO₄)₂ .H₂O]. Despite its excellent history as a P source, its use has declined as other P fertilizers have become more popular.
Evaluate the yield response of canola to MicroEssentials® S15® (13-33-0-15S) compared to MAP (11-52-0) + AS (21-0-0-24S) and MAP.
Potatoes are grown in nearly every state in the U.S., with sales in excess of $3 billion. Yield, tuber size and specific gravity (dry-matter content) influence quality factors such as frying properties and flavor. Fertility management decisions can influence these as well as storage properties.
When it comes to phosphate source selection, the menu is a good one. It contains liquid sources, such as the polyphosphates 10-34-0 and 11-37-0; and granular sources such as monoammonium phosphate (also called MAP, which is 11-52-0) and diammonium phosphate (also called DAP, which is 18-46-0).