June 2003 Nutrient Management
Protocol for Ontario Regulation 267/03 Made under the Nutrient Management
|Hydrologic soil group (see Ontario Ministry of Agriculture and Food Publication 29 Ontario Drainage Guide)||Maximum sustained field slope1 within 150 metres from the top of bank of surface water|
|At least 3% but less than 6 %||At least 6% but less than 9 %||At least 9% but less than 12 %|
|A (Rapid)||Very Low||Low||High|
|C (Slow)||Moderate||High||No Application|
|D (Very Slow)||High||High||No Application|
|Runoff Potential (see Table 9.1. 1)||Maximum rate of single application to land if materials are applied to the surface of land (in cubic metres per hectare)||Maximum rate of single application to land if the materials are injected2, or incorporated3 into the land or if the land is pretilled4 (in cubic metres per hectare)|
1 "Maximum sustained slope" is defined in the Regulation as: "...the average change in elevation from the top to the bottom of a slope divided by the length of the slope expressed as a percentage, where the slope has a minimum length of 10 metres and where the slope is towards surface water".
2 "Injection" is defined in Part 1 of the Regulation as: "...the placement of nutrients below the surface of the soil of the land"
3 "Incorporation" is defined in Part 1 of the Regulation as: "...the mixing of nutrients into the surface of soil by tillage with a minimum depth of soil disturbance of 10 centimetres": (must occur within 24 hours of manure application).
4 "Pretilled" is defined in Part 1 of the Regulation as: "...land that is sufficiently disturbed by tillage to disrupt large cracks and pores that could conduct liquid materials into subsurface soil or tile drains" (must have occurred no more than 7 days prior to manure application).
Determining the slope of the land is a necessary part of determining application rates and setbacks within NMAN. As the slope increases (gets steeper), the risk of liquid manure runoff at or following the time of application increases, as does the risk of soil erosion that can carry phosphorus into surface water. It is required to determine the slope of the field, or part of field, if it is within 150 metres (500 feet) of surface water. For fields beyond this distance, the NMAN program uses a default slope value of 7%, which can be over-ridden by an actual slope measurement if desired.
Slope is expressed as a per cent in the regulation, rather than as degrees. Per cent slope is simply the change in elevation of the land over a horizontal distance of one hundred units. A field that drops half a foot in one hundred feet has a slope of 0.5%, which is quite flat. A field that drops 15 feet in one hundred feet has a slope of 15%, which is quite steep. To put this in context, the Ministry of Transportation recommends steep grade warning signs whenever the road grade exceeds 9% over a distance of 150 metres.
There are several methods to determine the slope of the land, including but not limited to:
The choice of a particular method will depend on the level of precision required, and the resources available to determine the slope. More precise methods are generally more expensive. Visual estimation of slope may provide adequate precision in many cases, but more precise measurements will be required where slopes are near the break points between different slope classes.
The construction and siting standards for wells are governed by Ontario Regulation 903 of the Ontario Water Resources Act, as amended. The definition of wells in that regulation includes water wells, oil wells, gas wells and test wells. In addition, setbacks for the land application of nutrients are specified in the Regulation under the Nutrient Management Act.
No nutrients are to be applied within 100 meters of any municipal well as per Part 6 of the Regulation.
"Surface Water" is defined in Part 1 of the Regulation as:
Note: The following are not "surface water" for the purposes of the Regulation: grassed waterways, temporary channels for surface drainage (such as furrow or shallow channels that can be tilled and driven through), rock chutes and spillways, roadside ditches that do not contain a continuous or intermittent stream, temporarily ponded areas that are normally farmed, or artificial bodies of water intended for the storage, treatment or recirculation of runoff from farm-animal yards and manure storages,
"Obligate hydrophilic plants", which are mentioned in the definition for "surface water" are defined in the Regulation as: "...plants that require the presence of surface water or continuously saturated soils for their survival".
"Facultative hydrophilic plants" means plants that thrive in, but do not require the presence of, surface water for continuously saturated soil;
"Wetland", which is mentioned in the definition for "surface water", has the same definition as in Ontario Regulation 140/02 made under the Oak Ridges Moraine Conservation Act; namely: ...land such as a swamp, marsh, bog or fen (not including land that is being used for agricultural purposes and no longer exhibits wetland characteristics) that,
"Top of a bank of surface water", which is referred to in the paragraph below, is defined in the Regulation as:
Minimum setbacks from the top of bank of surface water are provided in Part 6 of the Regulation and depend upon a number of factors, such as the type of nutrient proposed to be applied to the land. Despite this, however, even greater setbacks may be required by the nutrient management plan as a result of nutrients containing phosphorus as indicated by the P. Index or the prescribed material application rate, in which case, the greater setbacks would apply.
In some circumstances, application of agriculture source materials to the soil without incorporation is allowed where at least 30% of the soil surface is covered with crop residue at the time of application. This is allowed for in Part 6 of the Regulation.
The percent of crop residue cover can be determined using the rope transect method. The material required is a light rope (about 8 m in length) with knots or other markings spaced along the rope at 15 cm intervals so that there are a total of 50 knots. This rope is laid out across the soil surface, preferably at an angle to the crop rows, and pulled slightly taut. The number of knots that are touching pieces of crop residue (minimum dimensions 2 mm by 2.5 cm) is counted. This number, when multiplied by two, is the percent crop residue cover. This determination should be made a minimum of four times in different parts of the field, and the results averaged.
Application of nutrients during the winter is undesirable because there is no growing crop to absorb the applied nutrients and there are often conditions that could lead to the runoff of applied materials into surface water. Restrictions to the application of prescribed materials during the winter are outlined in Part 6 of the Regulation. If winter spreading is contemplated in the nutrient management plan, then there must be a written explanation attached to the plan to justify such a scenario.
The following chart explains the restrictions that are set out in Part 6 of the Regulation.
|Type of material for application||From December 1 of one year to March 31 of the next year: soil not snow covered or frozen||Any time of year when the Soil is snow covered or frozen|
|Liquid agricultural source materials||
|Solid agricultural source materials||
|Non-agricultural source materials, excluding sewage biosolids and paper mill biosolids||
|Sewage biosolids||No application permitted.||No application permitted.|
Permanent vegetation in a buffer zone adjacent to surface water slows down the movement of runoff into surface water, filters out sediment and other particulate matter and absorbs nutrients that would otherwise enter the surface water. These will all have a positive effect on surface water quality. The Regulation requires that all surface water in fields (other than those fields comprised of organic soils) where nutrients will be applied, be bordered by a vegetated buffer zone which is defined in the Regulation as an area that:
This requirement is phased in, so that a farmer is required to have vegetated buffer zones at the same time as he or she is required to complete a nutrient management plan. Until the buffer is established, nutrient applications are subject to a wider setback from surface water as set out in Part 6 of the Regulation. Commercial fertilizer may be applied as required to establish the vegetation in the buffer. The maintenance of the buffer may use commercial fertilizer if it is applied according to:
Part 6 of the Regulation prohibits the application of prescribed material to land unless there is at least 30 centimetres of "unsaturated" soil condition at the surface of the land.
"Unsaturated", in relation to soil condition, refers to a soil water content that is less than 100 per cent of the total pore space, or that is at a negative soil water pressure as determined according to the following procedure:
|Creation Date:||30 June 2003|
|Last Reviewed:||30 June 2003|