The Using Manure Nutrients for Crop Production publication (PMR 1003) has recently been updated with revised beef cattle and dairy manure nitrogen (N) and phosphorus (P) crop availability ranges (Table 1, page 4). As shown below (bold values indicate revisions), beef cattle and dairy N availability ranges are now 30-50 percent of total nutrient applied and P ranges are 80-100 percent of total nutrient applied.
Beef cattle (solid or liquid) 30-50 80-100
Dairy (solid or liquid) 30-50 80-100
Changes were made based on current research results from Iowa and neighboring states.
In addition to the change in nutrient availability ranges, this text was added at the end of the section “Manure Nutrient Availability Values” (page 4):
“The ranges in nutrient availability are provided to account for variation in the proportion of organic and inorganic N and P forms, bedding type and amount, manure sampling and analysis variation, and application importance at different P and K soil test levels. See the footnote in Table 1 for further information on variability in manure nutrient availability.”
The publication also includes the new URL for the revised Corn Nitrogen Rate Calculator website.
The Using Manure Nutrients for Crop Production publication includes information about manure nutrient availability for crops, manure nutrient supply, manure nutrient application recommendations, adjusting for manure nitrogen volatilization, and more. You can download the revised document online for free at the Extension Store.