Page 179 - Nutrient Management Planning Guide

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Chapter 4.4

The following examples may help as a guide in determining the slope of the land:

- 4% slope is equal to a 3.6 m rise over a 90 m horizontal distance

- 6% slope is equal to a 5.4 m rise over a 90 m horizontal distance

- 12% slope is equal to a 10.8 m rise over a 90 m horizontal distance

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Table 4.4.2 Setback Distances from a Common Body of Water for Manure Application on Forage, Direct-seeded and Frozen or Snow-covered Land

Average slope within 90 meters of a common body of water

Setback distance required from the common body of water

4% or less 30 m Greater than 4% to less than 6% 60 m 6% or greater, but less than 12 % 90 m If the slope is 12% or greater, do not apply manure on the land. Once the slope is less than 12% manure can be applied.

Setbacks for manure application on land with less than 12% slope (on forage, direct-seeded crops, frozen or snow-covered land)

Setbacks for manure application on land with 12% slope or greater (on forage, direct-seeded crops, frozen or snow-covered land)

Figure 4.4.2 Slope-based manure application setback distances from common bodies of water on forage or direct seeded land.

Soil Nitrate-Nitrogen Limits

Under AOPA, soil NO

3

-N limits have been set for the top 60 cm of soil. The maximum allowable level depends on productive potential of the soil group, soil texture, depth to water table and soil type (Table 4.4.3).

Table 4.4.3 Soil Nitrate-N Limits for Agricultural Soils in Alberta

Soil

Soil Texture Coarse Textured Soils

(i.e., > 45% sand) Medium

and Fine Textured Soils

Depth to Water Table < 4m

Depth to Water Table > 4m

Brown 80 kg/ha 140 kg/ha 140 kg/ha Dark Brown

110 kg/ha 140 kg/ha 170 kg/ha Black 1-40 kg/ha 170 kg/ha 225 kg/ha Gray Wooded (Gray Luvisol)

110 kg/ha 140 kg/ha 170 kg/ha

Irrigated 180 kg/ha 225 kg/ha 270 kg/ha

Adapted from: Schedule 3, Standards and Administration Regulation,

2006

To convert the values from Table 4.4.3 from kg/ha to lb/ac, multiply by 0.89.

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