A number of potential mitigation measures for farmers affected by changes to nitrates regulations are to be sent to the European Commission for approval.
Following a meeting of the Agriculture Water Quality Group yesterday (Thursday, February 29) Minister for Agriculture, Food and the Marine, Charlie McConalogue announced proposed adjustments to the way nitrogen (N) excretion rates from calves and cows will be calculated.
In a statement, he said the changes “whilst relatively modest will benefit enterprises and farmers while also protecting water quality”.
The Department of Agriculture, Food and the Marine (DAFM) last October asked Teagasc to carry out research on bovine nutrient excretion rates.
According to Minister McConalogue this included analysis of the excretion rate of calves and the impact that reducing crude protein in concentrates fed to dairy cows has on the cow’s nutrient excretion rate.
The findings were reviewed and validated by University College Dublin (UCD).
But what effect will these changes have for dairy farmers who have already been affected by the changes to the nitrates derogation and the introduction of banding?
Using two sample farms – before and after the potential mitigation measures – this was outlined by the Irish Creamery Milk Suppliers’ Association (ICMSA) president Denis Drennan in Cavan in January.
Mitigation measures
The first example is a dairy farm with a total of 45ha (111ac), with 100 cows, 20 replacement heifers, 80 calves sold at six weeks and 20 heifer calves.
The farm has an average production of 5,000L/cow which places it in band two.
Currently the stocking rate of this farm is as follows:
- 100 cows (92kg x 100) = 9,200kg of organic N;
- 20 replacement heifers (57kg x 20) = 1,140kg of organic N;
- 80 calves, on farm for six weeks (24kg (divided by 52 weeks) x 6 x 80) = 221.5kg of organic N;
- 20 replacement calves (24kg x 20) = 480kg of organic N.
Based on these figures, the total organic N on this farm is 11,041.5kg, which means that the farm is stocked at 245.36kg of organic N/ha, placing this farm over the current limit of 220kg of organic N/ha and close to the previous limit of 250kg.
Using the proposed mitigation measures such as reducing crude protein in the concentrate, changing the N excretion figure for the calves and heifers, this farm could get down to 228kg of organic N/ha.
Stocking rate of farm after adoption of mitigation measures:
- 100 cows (87kg x 100) = 8,700kg of organic N;
- 20 replacement heifers (55kg x 20) = 1,100kg of organic N;
- 80 calves, on farm for six weeks (1kg (divided by 12) x 6 x 80) = 40kg of organic N;
- 20 replacement calves (21kg x 20) = 420kg of organic N.
This would reduce the total organic N of the farm down to 10,260kg and would mean an organic stocking rate/ha of 228kg.
The farm would have a reduction of 781.5kg of N being levied on this sample farm in band two.
This farm would still be required to get below the 220kg maximum stocking rate under the nitrates derogation, but this could be much more easily achieved.
For this sample farm, getting below 220kg could be achieved by culling four cows, exporting slurry or acquiring 1.6ha of land.
On this farm reducing the excretion rate of the cows to 87kg of N, is the equivalent of almost nine cows that this farmer would not have to cull.
Nitrates example two
The second example is a dairy farm with 49.8ha (123ac), with 100 cows, 20 replacement heifers, 80 calves sold at six weeks, and 20 heifer calves.
The farm has an average production of 7,000L/cow which places it in band three.
Currently the stocking rate of this farm is as follows:
- 100 cows (106kg x 100) = 10,600kg of organic N;
- 20 replacement heifers (57kg x 20) = 1,140kg of organic N;
- 80 calves, on farm for six weeks (24kg (divided by 52) x 6 x 80) = 221.5 kg of organic N;
- 20 replacement calves (24kg x 20) = 480kg of organic N.
Based on these figures, the total organic N on this farm is 12,441.5kg, which means that the farm is stocked at 249.8kg of organic N/ha.
Once again, this places this farm over the current limit of 220kg of organic N and close to the previous limit of 250kg.
Using the same proposed mitigation measures as the previous farm, the organic N stocking rate of this farm could be reduced to 228.1kg of N/ha.
If the changes being sought by the ICMSA were adopted:
- 100 cows (98kg x 100) = 9,800kg of organic N;
- 20 replacement heifers (55kg x 20) = 1,100kg of organic N;
- 80 calves, on farm for six weeks (1kg (divided by 12) x 6 x 80) = 40kg of organic N;
- 20 replacement calves (21kg x 20) = 420kg of organic N.
This would reduce the total organic N of the farm down to 11,360kg and would mean an organic stocking rate/ha of 228.1kg.
The adoption of these measures would result in the total N levied on this farm reducing by 1,081.5kg.
Again the farm would still need to adopt more measures to get below the 220kg of organic N limit, but this could be achieved by adopting one of three measures – culling six cows, exporting slurry or acquiring 2.7ha of land.
For this farm, reducing the excretion rate of the cows from 106kg to 98kg would result in the saving of equivalent of 11 cows.
Europe
The proposed measures have yet to get European Commission approval and it could be mid-summer before this happens.
It is believed that the measures would be back-dated for the year, if and when they are approved in Europe.
The two examples above looked at farms that have been impacted by the drop from 250kg to 220kg of organic N under the nitrates derogation – but they could also be significant for a different cohort of farmers.
These measures could also be quite significant for farms operating near the 170kg of organic N limit.
Changes to N excretion rates of cows and the introduction of banding has meant that many farms have moved into derogation.
The measures could once again move these farms out of derogation, if they are adopted at European and farm levels.