Factor 3: Current Soil Nutrient Levels, Soil Type, and Topography of the Land Base If soil nutrient levels are already high, nutrient additions from manure could be limited. The best way to determine the nutrient levels in the soil is to submit a soil sample for analysis. Soil type and topography can also limit the land base capacity for manure due to the higher risk of occurrence of contaminated runoff from soil with low soil infiltration and steep slopes. Factor 4: Proximity to Watercourses or other Environmentally Sensitive Areas In order to reduce the risk of surface or well water contamination, setbacks for manure application are used. These setbacks should be considered when calculating how much land remains for manure application. Manure Application Setbacks in Ontario • 330 ft. (100 m) from municipal wells • 50 ft. (15 m) from drilled wells (minimum depth of 20 metres and a watertight casing to a depth of 6 metres below ground level), • or 100 ft. (30 m) from any other well • 10 ft. (3 m) to 200 ft. (60 m) from the bank of surface water). This setback depends on a number of factors such as the incorporation method used, the slope near the watercourse and the P Index value.
Competency Area 3 Crediting the Nutrients in Manure for Crop Production Performance Objective 9 Use the availability factors for the nitrogen (current and previous applications), phosphorus and potassium in manure (e.g. published in Agronomy Guide for Field Crops and NMAN3). The best way of determining the amount of each nutrient from manure is to analyze a sample. Unfortunately, this is not always possible, as in the case of a new barn. In this case, average values will provide an estimate of the nutrients available to the crop. Nitrogen uptake by crops is in the mineral form as either nitrate (NO3-) or ammonium (NH4+). This means the ammonium portion of the manure is immediately available to the crop while the organic nitrogen needs to be mineralized before it can be used. For optimum use of the nutrients in manure, they should be available where and when the crop can utilize them.
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PROFICIENCY AREA V - Manure Management