Using a slurry testing kit and flow meter can save farmers up to £265 per hectare in fertilisers. “If you don’t know the nutrient value of your slurry and the rate it is being spread at then the financial savings and crop benefits are guess work,” says Terry Baker from slurry specialists Tramspread.
A nitrogen meter such as the Agros Nova Mk3 can test slurry and manure for plant available nitrogen (N) in just five minutes. “These kits only cost £425 and offer farmers a lab test accurate reading of kilos of plant available N per cubic metre,” says Mr Baker. Once aware of the nutrient value, farmers can begin to calculate the volume of slurry required for the crop and use a flow meter to spread accurately.
The Tramspread Isobus flow meter package costing £3,740 is one of the most accurate methods of measuring slurry application. It connects a flow meter to the tractor’s GPS and can be used to adjust the application rate from the cab. “Combining field maps, choosing the application rate and recording the amount of slurry applied will give the operator an accurate report of the amount of slurry applied per hectare,” says Mr Baker. When this technology is coupled with accurately tested slurry it also offers farmers a way to measure the cost benefit of slurry application to the farm.
The data in AHDB’s RB209 nutrient management guide helps to illustrate the savings available by testing slurry and applying it accurately. “Calculating the available nitrogen, phosphate and potash (N, P and K) of slurry can save significant sums of money. ADAS soil scientist John Williams has used the RB209 guide to equate this to between £215 and £265/ha, based on a season’s application of 95m3/ha of cattle slurry,” says Mr Baker.
“Slurry is one of the most undervalued resources farmers have. If stored, tested and applied carefully with attention to nutrient value, slurry offers significant savings and environmental benefits,” concludes Mr Baker.
