ARCHIVE: Nitrate Vulnerable Zones (NVZs) - Guidance for Farmers. Standard values, manure sampling (Leaflet 3 - PB12736c)

3. Standard values and information needed to determine the nitrogen content of organic manures

You can use either the standard values provided in Table 7 or manure sampling and analysis (see the 'Protocol') to determine the total nitrogen content of imported or exported livestock manures when assessing your compliance with the livestock manure N farm limit (follow the calculations in Leaflet 5). To note: when calculating the total nitrogen content of manures produced by livestock kept on your farm for the livestock manure N farm limit you must use the standard figures in Tables 1 - 4. These figures have been derived differently from those provided in Table 7, as they are used for different purposes, and therefore are not directly comparable.

Table 7 also provides a figure for the maximum application rate that would supply the maximum amount of total N permitted under the organic manure N field limit of 250 kg N/ha/yr (follow the calculations in Leaflet 8). To note: these figures are provided for guidance only and you should determine a suitable application rate for your specific circumstances.

Table 7 contains data for goat farmyard manure and horse manure. These were not shown in Schedule 2 in the Regulations, from which the table is derived, but if these figures are used it will not be considered a breach of the rules.

Table 8 must be used when calculating 'crop available N' from any livestock manure applications when assessing your compliance with the N max limit (follow the calculations in Leaflet 7).

Table 7: The total N content of organic manures and maximum application rates to supply 250 kg N/ha of total nitrogen

Manure type Total N content kg/m3 or kg/t The maximum application rate to supply 250 kg N/ha
Metric Units Imperial Units
Solid manure
Cattle farmyard manure 6.0 42 tonnes/ha 17 tons/acre
Pig farmyard manure 7.0 36 tonnes/ha 14.5 tons/acre
Sheep farmyard manure 6.0 42 tonnes/ha 17 tons/acre
Duck farmyard manure 6.5 38 tonnes/ha 15 tons/acre
Poultry layer manure 16 16 tonnes/ha 6.5 tons/acre
Poultry broiler litter 30 8 tonnes/ha 3.2 tons/acre
Turkey litter 30 8 tonnes/ha 3.2 tons/acre
Horse farmyard manure 7.0 36 tonnes/ha 14.5 tons/acre
Goat farmyard manure 6.0 42 tonnes/ha 17 tons/acre
Slurry
Dairy cattle 3.0 83 m3/ ha 7,400 gallons/acre
Beef cattle 2.0 125 m3/ ha 11,200 gallons/acre
Pigs 4.0 63 m3/ ha 5,600 gallons/acre
Separated manures
Separated cattle slurry, liquid fraction, strainer box 1.5 167 m3/ ha 14,900 gallons/acre
Separated cattle slurry, liquid fraction, weeping-wall 2.0 125 m3/ ha 11,200 gallons/acre
Separated cattle slurry, liquid fraction, mechanically separated 3.0 83 m3/ ha 7,400 gallons/acre
Separated cattle slurry, solid fraction 4.0 63 m3/ ha 5,600 gallons/acre
Separated pig slurry, liquid fraction 3.6 70 m3/ ha 6,300 gallons/acre
Separated pig slurry, solid fraction 5.0 50 m3/ ha 4,500 gallons/acre

Table 8: The percentage of the total nitrogen content of livestock manures that is available for crop uptake in the growing season in which it is spread to land (i.e. crop available N)

Manure type Crop available N
(% of total N applied)
until 1st January 2012
Crop available N
(% of total N applied)
from 1st January 2012
Cattle slurry 20 35
Pig slurry 25 45
Poultry manure 20 30
Other livestock manures 10 10

Note: Only for use in the N max calculation.

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