The latest current and up to date advice
August is a good month to sort out deficits in grazing infrastructure to optimise days at grass, if your capital expenditure budgets allow. Helpful solutions include spur roadways, multiple access points to paddocks and back fencing.
When it comes to grazing infrastructure on farms, there is usually a list the length of your arm that needs time and money to complete. But the reality is, if you don’t make time for that list now, when will you? Apart from holidays, this time of year is generally quieter and dry conditions make it ideal for tackling infrastructure on your farm.
The reason you should aim to have excellent grazing infrastructure is that it enables you to keep livestock out grazing for a lot longer in the autumn and spring. Every day at grass in the Autumn for 100 LU (livestock units), earns you €200 per day. This figure comes from the difference in feed costs and extra animal performance from grass. So it is an expensive toll to pay for not having the right infrastructure in place.
Excellent grazing infrastructure is when a farmer and their livestock can move easily from paddock to paddock or paddock to farmyard without difficulty. This usually requires all paddocks to have multiple access points onto a roadway. This access can be to a central farm roadway or a smaller spur roadway, but either way it is a smooth hard surface capable of withstanding animal traffic during difficult weather conditions. Pigtails and reels are essential to set up stripwires. These allow stock graze a portion of a paddock for a short period (12hrs) to avoid poaching. Ideally these sections will still having access to a roadway without going back over area already grazed. Repositioning water troughs may also be necessary to facilitate this.
The paddocks closest to the farmyard are usually well equipped. It is the paddocks further away, awkwardly shaped, wetter, silage ground, etc., that are usually less equipped to enable an extended grazing season. Start with the low hanging fruit that give you the best bang for your buck, after all it is an investment which will pay you back. Remember you’ll never meet another farmer that regretted putting in a roadway!
Extra grazing days in the autumn are achieved by building grass cover during August. Extra days at grass will result in less silage in the diet reducing methane emissions; less slurry management required and improved efficiency.
Key tips for building grass in Autumn:
- Establishing stocking rate and what targets you need to hit;
- Aiming to extend rotation from the 10th August;
- Avoid making surplus bales beyond early August to allow sufficient regrowth of grass for Autumn build-up;
- Control demand by introducing supplement or reducing stocking rate;
- Apply protected N + K protected, in line with your NMP
Autumn Covers - Lets Talk Dairy Webinar (50 minute duration)
To build Autumn grass, spread 20-25 kg N / ha using protected urea in the last 2 weeks of August when you get the best response in grass growth. Matching N application to grass growth optimises the efficiency of N and reduces GHG emissions.
Every effort should be made to apply nitrogen (N) where required sooner rather than later. As we move from August to September to October the response to applied fertiliser N will decline.
Late Season N Response Studies
Fertiliser N studies conducted over the last 3 years at four sites in Wexford, Cork, Louth and Mayo within the Agricultural Catchments show the average response to per kilo of N applied during August, September and October were 27kg, 19kg and 10kg respectively (figure 1).
Response to applied late N fertiliser
- Average grass growth in August was 27kg DM per kilo of N applied. Grass dry matter yield response to applied N reduces by 30% in September and 63% in October.
- Currently N costs €1/kg. The N cost for growing a kg of grass DM in August and early September is 3 to 5 cent per kilo. Grass grown from N fertiliser applied in later September costs approximately 10c per kilo.
- Earlier applied N results in greater grass growth and more efficient use of each kilo of N.
- Apply cattle slurry to meet grass fertiliser demands and empty slurry tanks before winter.
- Apply 30 kg N/ha on grazing ground to build grass covers.
- Where grass will be cut for silage apply 60kgN /ha depending on grass yield potential.
Empty your slurry tanks empty. Managing your slurry over the winter to be able to spread the slurry when you will get the maximum value from it in Spring starts now.
In an environment, where chemical fertilisers are expensive and where their use is going to be subject to increased regulation, farmers must use slurry as the Number 1 source of nutrients on the farm. Only then should you top up with chemical fertiliser to meet your crop requirements.
Spreading slurry in mid-January when there is no grass growth and soil temperatures are very low is a waste of nutrients. The correct time of the year to spread slurry is when grass is actually growing. For most soils this is when soil temperature is greater than 5-6o Celsius. For dry soils, this could be late January in a warm dry spring. For heavy or peat soils, this could be early to mid-March.
Emptying your tanks now will reduce the risk of storage issues over the winter, allowing you to optimise the value of this nutrient in Spring.
If feeding ration with grass only - feed maximum 14% CP. Less excess protein in the diet means less N excreted and less GHG emissions. The protein content of Autumn grass is high, greater than 20%. The requirements of mid/late lactation animals or finishing animals for protein is met by grass only. Energy is the most limiting nutrient in this type of grass, supplement with energy and low protein.
Check milk recording and bulk milk health screening reports or faecal egg count reports for issues that need to be resolved. Healthy animals means increased animal performance, reduced replacement rate and fewer non-milking animals, reducing GHG emissions per kg of milk produced.
These reports provide valuable information on your herd and are an important decision support tool for making health decisions on your farm.
Climate Actions for July
Oversown Clover Swards
Graze swards that have been over sown at 800 kg DM/ha on the first grazing. At 1100 for the following three grazing rotations, with a post-grazing sward height of < 4 cm. Avoid building high pre-grazing covers of these swards for the remainder of the year. Close later in the final grazing rotation, as this allows light to the base of the sward. This is essential for the clover plant to establish and persist. Nitrogen fertiliser can be reduced for the first 2 applications after over-sowing to aid the clover plant become established. For the remainder of the year, normal fertiliser rates should be applied, as the clover plant required nitrogen to help in plant development. Once these swards are 12 months old, and there is adequate clover content (20-25%), nitrogen fertiliser can be reduced.
Reduce N Fertiliser
For existing white clover swards reduce application rate of fertiliser over the summer to promote clover establishment.
Nitrogen fertiliser application strategy
|Rotation/date||Grass 250kg||Grass-Clover 150kg|
|April - 2nd rotation||33||33|
|May - 3rd rotation||30||9|
|May - 4th rotation||30||9|
|June - 5th rotation||17||9|
|July - 6th rotation||17||9|
|July - 7th rotation||17||9|
|August - 8th rotation||17||9|
Have adequate slurry storage
Having adequate slurry storage and including a buffer offers many advantages including:
- More flexibility to match slurry application timings with grass growth.
- Better use of nutrients when grass is growing.
- To better manage increased rainfall events at the shoulders of the year.
- To provide cover for miscellaneous issues where water enters tanks and reduces capacity.
- To have enough storage to meet the regulations and a buffer of 20% to cover miscellaneous occurrences.
- To use slurry to replace one round of chemical fertiliser/year.
- To apply slurry at the correct time to maximise the fertiliser replacement value (N, P and K) of slurry.
- To take advantage of the TAMS grants available to farmers for additional slurry storage of 40-60%. The cost can also be written off against tax and the VAT is reclaimable. More details on slurry storage Slurry storage - have you enough? (PDF)
Restore nutrients after silage
A typical bale of silage weighing 800kg fresh (200kg dry matter) contains 10 units of nitrogen (N), 1.6 units of phosphorus (P) and 10 units of potash (K). For example where surplus bales are removed, four to five bales of silage per acre will remove six to eight units of P/ac and 40 to 50 units of K/ac. Apply thick slurry and protected urea compound (includes K) to restore nutrients, in particular K.
Use LESS equipment to spread slurry
Farmers should use slurry as the number one source of nutrients on the farm. Spreading slurry by LESS will increase the availability of nutrients and reduce gaseous emissions. LESS retains an extra 3 units of N / 1,000 gallons of cattle slurry. Most contractors have both the traditional splash plate and LESS equipment, its up to farmers to ask their contractor to use LESS.
Review your fertiliser plan
It’s a good time of the year to review your fertiliser plan. Too often these plans are used for regulation purpose rather than helping improve soil fertility on the farm. Take a look at the liming map, the P map and the K map to identify fields that need some extra work.
Time for Lime – Low Cost Fertiliser
Now is the ideal time to apply lime to correct soil pH on mineral soils. Lime will bring many benefits from increasing the availability of soil nutrients (N, P, K & S) to improving soil structure (aeration & drainage). Soils maintained at a soil pH 6.3 to 6.5 will release up to 70kg N/ha/year from soil organic N reserves. This will help reduce chemical fertiliser nitrogen (N) bills on farms by approximately €70/ha/year. Lime will increase the availability of soil phosphorus (P) and is the first step to improving / building soil P levels cost effectively. Maintaining the optimum soil pH will in addition increase the response to applied N, P & K in either organic manures such as cattle slurry / FYM and N, or bag fertilisers such as 10-10-20 / 18-6-12 etc.
Over the coming days / weeks check soil test results and apply lime to fields based on lime recommendations. Target fields with the lowest soil pH first and apply lime where the opportunity presents for example after grazing paddocks, 2nd / 3rd cut grass silage or at reseeding time. Soils maintained at the optimum soil pH 6.3 will grow approximately 10 to 15% extra grass during the growing season. Ground limestone is the cheapest and most cost effective tool to control soil acidity in the long term. Apply a maximum of 7.5t/ha (3t/ac) ground limestone in a single application.
Apply potassium to low K Index soils
Approximately 60pc of our soils nationally are at index 1 and 2 for potassium. This means that six out of 10 silage fields are deficient in potassium, and this poses a challenge. Autumn time is the ideal time of year to rectify potassium deficiencies. So why is potassium such an important fertiliser? Potassium is the nutrient taken up in the greatest quantity by grassland swards and has a wide-ranging role in the plant, affecting nutrient uptake, photosynthesis, rate of growth and feed value.
It is particularly important for increasing stem strength, improving drought resistance and cold tolerance, and importantly for increasing yield.
Potassium fertilisation is vital, especially in autumn and on older grass. If adequate amounts of potassium are not available, the rate of growth and yield will be restricted.
There is also a relationship between nitrogen and potassium, as the response of grass to nitrogen is dependent on an available supply of potassium to allow N uptake as nitrate and conversion into proteins.
In silage fields in particular, stem strength is of huge importance. Silage crops low in potassium are more prone to lodging, as the stem cannot hold up the seed head and grass plant.
Padraig O'Kiely's work in Teagasc, Grange on the factors that impact most on silage quality show that lodging is the factor that can lead to the greatest deterioration in the quality of a silage crop and estimates that up to nine units of DMD percentage could be lost by your crop lodging. This means your 70pc DMD silage pit might now be only 61pc DMD.
In looking at the K requirements for 1st cut silage, index 1 and 2 soils for potassium require 120-140 units of potassium/acre.
However, as the recommended amount of K to be applied in a single application is 90 units (three bags 0-7-30/acre), the advice is generally to spread the 90 units and wait until the autumn to spread the balance. In practice, this balance is rarely spread.
The reason why it is advised to only spread 90 units in a single application is because luxury uptake of potassium occurs in rapidly growing spring grass, which has the ability to take up a lot more potassium than it needs for normal plant functioning.
High levels of potassium in the plant interfere with the uptake of magnesium, and low magnesium in the animal's diet is one of the factors causing grass tetany.
Many of us depend on cattle slurry to rectify our potassium deficiencies; as 1,000 gallons of thick cattle slurry will contain approximately 30 units of K, it will go some distance to replacing some of the K off-take from cutting or grazing.
However, in a silage situation, 3,000 gallons/acre provides only 90 units of K at best, meaning we are still short 30-50 units of K on index 1 and 2 soils. The Autumn is the best time to apply this amount.
It is vital to replenish this K to ensure next year's silage crops will grow to their potential and help fill the empty silage pits around the country. A bag of Muriate of Potash (50 units K) should be adequate in most situations.
As there is no legal deadline or maximum rates in relation to potassium, every farmer should look at getting a pallet or two of potassium spread over the next month.
September is the last month you have to build grass covers and extend your grazing rotation length in order to set your farm up for the last grazing rotation in October and November. If you don’t have a reasonable bank of grass saved up by the end of the month, your last rotation could end up being very short and you will have to house all of your stock much sooner than you would like to. September 15 is the last day you can spread nitrogen (N) and phosphorus (P) fertilisers. The sooner any planned fertiliser applications are spread the better, as growth rates tend to decline as the month progresses. No more topping or surplus silage cutting should take place. Dairy cows can be supplemented with meals to allow grass to build. Suckler cows being weaned can be restricted to allow covers to build, especially if they are already in good body condition. Stock being finished off grass should be supplemented with meal, which will reduce their demand for grass. Young calves in dairy calf-to-beef systems should be fed meal at grass from now until housing. Replacement heifers below target weight should also be supplemented. The target going into October and the last grazing rotation should be to have at least 35 days of grass ahead of stock. If weather conditions allow it, this would mean that some stock will be grazing until November.
In summary, if below target-:
- Reduce demand with meal and silage. Feed high quality baled silage for 7-10 days. Use a strip wire to allocate grass
- Remove cull and empty cows from the herd
- Rotation should be at 35 days from mid September. 120 acre grazing platform should be grazing 3.5 acres per day and the deficit filled with meal and silage
Autumn Grazing Targets
Average Farm Cover
|STOCKING RATE OF 2.5 LU/HA|
|1st August||180||450||20 Days|
|1st September||300||750||30 Days|
|1st October||400||1,000||40 Days|
|1st November||60% of your grazing platform should be closed for Spring at this stage
|STOCKING RATE OF 3.0 LU/HA|
|1st September||330||990||30 Days|
|1st October||380||1150||40 Days|
|1st November||60% of your grazing platform should be closed for Spring at this stage|
|STOCKING RATE OF 3.5 LU/HA|
|1st September||280||980||30 Days|
|1st October||335||1175||40 Days|
|1st November||70% of your grazing platform should be closed for Spring at this stage|
Weigh replacement heifers now
Every year when it comes to selecting replacement heifers with a target to calve at 24 months it becomes apparent that significant number won’t make ‘the cut’. It is obvious in many cases that these heifers are not achieving the weight for age targets at bulling. Hence, they are left to grow on and calve at 36 months. Research undertaken by Teagasc shows that delaying calving from 24 months up to 31-32-months for beef cows, costs approximately €490 or €50/heifer/month mostly in the form of feed costs. On dairy farms the cost of heifers not calving down at 24 months is approximately €70 / head.
Weighing animals in September will help to identify issues with poor weight gains and allow you to take action before housing. This may mean feeding supplementary concentrate to supplement Autumn grass and / or implementing a dosing programme to sort out worm / fluke problems.
Target Weights for Dairy Replacement Heifers
|Maintenance sub index|
|% of mature weight||€10||€20|
|6-month weight||30%||177 kg||162 kg|
|Pre-breeding weigth||60%||354 kg||324 kg|
|Pre-calving weight||90%||531 kg||486 kg|
|"Mature weight"||590 kg||540 kg|
Beef Heifer Weight for Age Targets
|Mature Cow Weight||
|Target % of mature cow weight||60%||80%|
|600 kg||260-280 kg||360 kg||480 kg|
|700 kg||300-320 kg||420 kg|
Research at Teagasc Grange has shown that single-suckled beef calves supplemented with concentrates prior to weaning were less immune-compromised, started consuming meal faster when housed indoors, and spent more time lying down (rather than standing and walking) post-weaning compared with non-supplemented calves.
At pasture: Introduce concentrates one month prior to weaning sucklers and gradually increase the allowance with the intention of having the calf consuming one kg/day at weaning time. Continue to feed the concentrates for at least two weeks after weaning.
If feeding supplementary concentrate to replacement heifers, energy is the most deficient nutrient in the Autumn. Feed a high energy low protein concentrate feed.
Dosing and Vaccination Programme
Calves should be treated for stomach worms and hoose during the grazing season and for Ostertagia Type II worms at housing using effective anthelmintics administered according to product recommendations. Calves with pre-damaged lungs from lungworm infestation also have a higher risk of developing pneumonia.
With spring calving suckler herds, weaning calves in September-October, now is the time to plan your vaccination programme. Catherine Egan, Teagasc Beef Specialist, highlights that the number one cause of mortality in weanlings in 2020 was pneumonia and she has advice to prevent it on your farm here. Click here for details
Changes in the regulations around antibiotic use means that from 28 January 2022, dairy farmers will no longer be permitted to use dry cow tubes on all cows in a herd at the end of lactation, unless they have evidence that they require them. There are only one more dry-off seasons before the new regulations come into place.
Milk recording will provide farmers with the evidence needed to show that antibiotics are required. Another advantage of milk recording is that it will show the actual number of cows to be treated and the success of the previous year’s dry cow treatment. If you have never recorded before, now is the time to start.
For a herd that hasn’t milk recorded before, is it too late to start now for this year?
For any herd, the best time to start milk recording is close to the start of lactation. For a herd that hasn’t ever milk recorded, the second-best time to start is now. The reason for this is that all milk recordings will build a build a profile of the mastitis spread and control
Who should I contact about recording?
To start milk recording, ring one of the following numbers:
Progressive Genetics 045-9540606
Munster Al 022-43228
Tipperary Co-op 062-33111
Where can I learn more?
Episode 120 of Teagasc’s Dairy Edge podcast featured an interview with Don Crowley, who discussed the mid-lactation mastitis challenge. Listen below.