10 Point Action Plan to Reduce Chemical Nitrogen Use in 2022
Step 1.
Lime ground in December/early spring where soil pH is low. Why? Land at pH above 6.3 and at index 3-4 for P and K can release up to 70 kg/N/ha per year every year.
Step 2.
Spread maintenance (Index 3) levels of P and K. Why? Taking a P and K holiday is a false economy as nitrogen use efficiency will be compromised.
Step 3.
Do a fodder budget now to conserve winter feed and carry feed stocks into 2022. Why? Managing silage now and carrying into 2022 will mean a lower requirement to make silage in 2022 and reduce pressure on chemical N for silage.
Step 4.
Match your stocking rate to your farm’s grass growing capacity. Can you sustain your current stocking rates at fertiliser costs of almost €200/cow in 2022? Why? The last 40% of fertiliser spread (100 kg/N/ha) on heavy stocked farms grows about 10% of the total grass grown. Can you cull empty cows/poor performers etc. for 2022?
Step 5.
Spread your slurry in the spring and preferably with low emission slurry spreading technology (LESS) and increase N recovery by 50%. Why?
Summer spreading using splash plate 3 units/1,000 gals
Spring spreading using splash plate 6 units/1,000 gals
Spring spreading using LESS 9 units/1,000 gals
Step 6.
Spread your slurry at a rate of 2,500 gallons per acre and target silage ground and lower fertility ground. Why? Spreading at a rate of 2,500 gallons/acre should give enough slurry for 50% of the farm and this rate can replace 20 units of chemical N/acre (enough for the first spreading).
Step 7.
Spread Protected Urea where possible as it has lower N losses and reduces greenhouse gas and Ammonia emissions. Why? Protected Urea is ordinary Urea treated with a Urease inhibitor that releases N at a slower rate. 20 units/acre of Protected Urea can give the same effective N as 23 units of Urea/CAN.
Step 8.
Cut the rate of the 2nd spread of fertiliser in March from 46 units to 40 units/acre. Why? Cutting the rate by 6 units/acre is the same as a 3% reduction over the year and this should not compromise grass growth.
Step 9.
A unit a day is ok. Cutting fertiliser to 20 units per round in the summer is ok. Why? Having 130 units/acre available from April onwards means spreading less than 1 unit per day for summer grazing season.
Step 10.
Incorporate clover at 2kg/acre in new reseeds and 2.5 kg/acre where over-sowing. Why? Incorporating clover in the long term can replace up to 100 kg/N/ha mainly from mid-summer onwards. Reduce chemical N on existing clover swards from May onwards.