Climate Actions for December

Read the latest farm advice and current actions farmers should consider taking this month

Protected Urea

Protected Urea is very welcomed news for Irish agriculture as it is a key technology for the sector in meeting its 25% reduction in GHG’s emissions by 2030.  It is seldom that a new technology costs less and delivers major environment benefits in reducing N losses. Extensive research in Teagasc and on farm use has shown the reliability of protected urea as a very effective N fertiliser source for Irish farming conditions. It delivers consistently on yield compared to nitrate based fertilisers (CAN 27% N) while significantly reducing nitrous oxide (N₂O) a powerful GHG and ammonia (NH3) emissions thus improving the efficiency of applied fertiliser N.

Urea fertiliser is the most widely used N source in the world and protecting it with a urease inhibitor (NPBT / NPPT) firstly reduces ammonia N (NH3) losses by up to 80% thus retaining more N to better match crop N demands during the growing season.  Secondly, by replacing nitrate-based fertilisers (e.g. CAN) with protected urea we reduce N₂O losses by 70%.  This is a major ready to go technology in meeting out 2030 target, delivering a 3 to 8% reduction in GHG emissions on livestock farms.

Cost savings €€€!

Over the last 24 months fertiliser N prices have reach heights never seen before due to global unrest.  This has resulted in a large price differential between protected urea and CAN, with urea significantly better value due to large volumes traded globally. Over the last 6 months, fertiliser prices have dropped month by month but remain high compared to pre global unrest.  Average fertiliser prices to date in 2023 (table 1) show that Protected urea offers a 30% lower cost per kilo compared to CAN (27% N).   Take a 50ha dairy farm applying 210kg N/ha as Protected Urea compared to 150 kg N/ha as CAN gives a saving in fertiliser N costs of €7,980.

Retaining more effective N & Reducing N rates

Protected urea reduces N loss from 15% for standard urea to 3% thus retaining 12% more effective N.  With reduced and more regulated chemical fertiliser N use, retaining more effective N in the soil allows adjustments to N rates while still maintaining yield compared to standard urea.  Take an example 50ha dairy farm switching from applying 210kg N/ha as all Standard Urea to Protected Urea, N rates can be reduced by 12% equating to a reduction of 22kg N/ha giving a fertiliser farm N saving of €1,936.

Reducing farm emissions

By switching to 100% protected urea on dairy farms, total farm emissions have the potential to be reduced by 7-8% at a spreading rate of between 200 to 250 kg N / ha. The equivalent savings on total emissions on suckler farms is 1-2%, at a spreading rate of 60 to 80 kg N / ha. To achieve a 100% switch to protected urea the use of high P-K products such as 18-6-12 +S would be required to deliver balanced P, K & S nutrition. On-going research at Johnstown Castle is showing that fertiliser blends containing N with a high ratio of ammonium-N to nitrate-N (generally high P blends) are more stable and environmentally friendly.   For example, the N form is 10-10-20 / 18-6-12 is mainly ammonium N resulting in a 40% reduction in N₂O emissions relative to CAN 27% N or  high Nitrate – N based compounds such as 27-2.5-5 / 24-2.5-10.

More grass from less N

A long-term trial (8 years) at Johnstown Castle is consistently showing that the grass grown by protected urea has been greater than standard urea in 7 out of 8 years.  Protected urea grew 13% more grass on average compared to standard urea.  The additional yield is similar in magnitude to the extra effective N level delivered to the plant by protected urea over standard urea. CAN yielded 9% more than standard urea.  At a time of more regulated chemical fertiliser N use moving from standard urea to protected offers the opportunity to reduce fertiliser N rates by up to 10%.

In Summary - Making the switch to Protected Urea delivers the following

• Reduce your fertiliser N costs by 30%
• Reduce N₂O & NH3 emissions by 70 and 80%, respectively
• Reduce overall farm emissions by 7 to 8%
• Fertiliser blends such as 18-6-12 reduce GHG emissions by 40%
• Reduce farm N requirements (Switch from Standard Urea to Protected Urea)
• Protected urea grows 13% more grass over standard urea

Soil Sampling

The results of a soil analysis are only as good as the sample on which it is based. To give reliable advice, a soil sample must be representative of the area sampled and be taken to a uniform depth (10cm).

The principle of soil analysis is to determine the average nutrient status of an area and to give a measure of the available nutrients in the soil. A sample normally consists of 0.25 – 0.5 kg of soil and this is taken to represent the entire sampling area or field.

1. To take a soil sample it is essential to have a suitable soil corer
2. Ensure soil cores are taken to the correct sampling depth of 100 mm (4”)
3. Take a soil sample every 2 to 4 ha. (5-10 acres)
4. Take separate samples from areas that are different in soil type, previous cropping history, slope, drainage or persistent poor yields
5. Avoid any unusual spots such as old fences, ditches, drinking troughs, dung or urine patches or where fertiliser / manures or lime has been heaped or spilled in the past.
6. Do not sample a field until 3 to 6 months after the last application of P and K and 2 years where lime was applied.
7. Take a minimum of 20 soil cores, mix them together, and take a representative sub-sample for analysis, making sure the soil sample box is full.
8. Take a representative soil sample by walking in a W shaped pattern across the sampling area.
9. Sample fields at the same time of the year to aid comparisons of soil sample results and avoid sampling under extremes of soil conditions e.g. waterlogged or very dry soils.
10. Place the soil sample in a soil box to avoid contamination and write the field number and advisor code on the soil box with a black permanent marker.

Soil Sampling Pattern

Weigh Finishing Animals and Heifers

Weigh finishing animals over the winter to ensure they are on target for finishing.

Invest in a weighing scales.  A weighing scales is an important decision support tool, helping farmers to make decisions around performance management. 

Weighing

1. Make sure the scales is correctly calibrated
2. Weigh finishing animals at housing and again midway through the housing period
3. Weigh animals at the same time every time you weigh them. Pick a time and stick to it. Gut fill can have a significant impact on weights so always do the weighing when they are either full or empty. 
4. Don’t put too much emphasis on weights taken close together e.g. every month. Weighings 2-3 months apart can give a more accurate picture.
5. Don’t put too much emphasis on the weight of individual animals. There will be significant variation in a group but the overall trend needs to be right.
6. Take action based on the weights. Things to watch for:

• Silage quality

• Silage intake

• Supplementation rate

• Supplementation quality

• Housing – space allowance, feeding space and ventilation

• Fluke and worm dosing programme

Plant New Hedgerows and Trees

Best practice hedge planting

• Mark out the line of the new hedge using wire, twine or lime
• Cultivate with a digger or mini-digger - to make it easier to plant and give plants a great start
• Protect roots from drying out during planting by keeping plants in the bag until needed
• Plant in a double staggered row – with 330mm (just over a foot) between the rows and the same between the plants within the rows – often the length of a boot
• Plant to the same depth as was previously planted. Don’t bury the stem or expose the roots
• Firm in
• Identify a few whitethorn (maybe 5 / 100 m) to be retained as trees and protect with tree guards or shelters
• Prune all other plants except holly down to an inch or so above ground level with a sloping cut to leave a sharp point
• Push a 4 foot or 1.2m wide strip of compostable film or used silage plastic down neatly over the cut stumps.
• Press the edges of the plastic into the ground to hold it down
• Protect from livestock including rabbits if The aim is to remove that wire in a few years

More information on Planting Hedges

Options to Import Organic Manures on Tillage Farms

Organic manures are a valuable and cost effective source of N, P & K especially with the large increase in fertiliser prices.  To maximise the recovery of N from high N manures (pig & poultry) it is important to apply and incorporate within 3 to 6 hrs. Ideally test manures in advance of application to know there nutrient values and adjust application rates to supply ~ 50% of the crops P & K requirements.  For example an application of 25mᶾ/ha of pig slurry (2,200gals/ac) can supply 52kg N, 20kg P & 50kg K/ha which is ~30% of N and ~50% of P & K requirements for a crop of spring barley.  Now is a good time to look at local sources of organic fertilisers and plan for spring crop utilisation.

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