The Water Resources (Control of Agricultural Pollution) (Wales) Regulations 2021

Calculating the amount of nitrogen available for crop uptake from organic manure

9.—(1) The occupier must establish the total amount of nitrogen in livestock manure, for the purposes of regulation 8, by—

(a)using the table in Part 1 of Schedule 3, or

(b)sampling and analysis in accordance with Part 2 of Schedule 3.

(2) Once the total amount of nitrogen in the livestock manure has been determined, the following percentages are assumed in order to establish the amount of nitrogen in the livestock manure that is available for crop uptake in the growing season in which it is spread.

Available percentage

Type of livestock manureAmount of nitrogen available for crop uptake in the growing season in which it is spread
Cattle slurry40 %
Pig slurry50 %
Poultry manure30 %
Other livestock manure10 %

(3) In relation to all other organic manure, the occupier must establish the total amount of nitrogen available for crop uptake in the growing season in which it is spread, for the purposes of regulation 8—

(a)by reference to technical analyses provided by the supplier,

(b)to the extent that such information is unavailable, by reference to the values given in the Nutrient Management Guide (RB209)(1), or

(c)by sampling and analysis in accordance with Part 2 of Schedule 3.

(1)

https://ahdb.org.uk/RB209. A copy can be obtained from AHDB (the Agricultural and Horticultural Development Board.