Department of Agriculture, Environment and Rural Affairs - Northern Ireland Government

04/08/2024 | Press release | Distributed by Public on 04/08/2024 08:47

Management notes for April 2024

Management Notes are prepared by staff from the College of Agriculture, Food and Rural Enterprise (CAFRE). CAFRE is a College within the Department of Agriculture,


Prepared by: David Mackey

Early season grazing management

As concentrate feed accounts for about two thirds of variable costs on dairy farms, making the most of your spring grass is a cost effective way of reducing costs. To manage grass effectively through the season, it is important to graze all the grazing platform by mid-April and establish a grass wedge before growth starts to take off by the end of April. Walk your grazing fields regularly to assess grass covers, ground conditions and swards in need of reseeding or rejuvenation.

Prepare a budget of grass supply and demand using a plate meter and a software programme, if necessary to produce a grass wedge. Rank fields from highest to lowest cover and identify grass surpluses or deficits. Dry swards with a cover of 2,500 kg dry matter (DM) per hectare or more (the ankle of your boot or higher) should be grazed out first to limit poaching. Ensure they are well grazed out, down to 1,500 kg DM per hectare (the heel of your boot) to maximise grass quality for subsequent grazing rounds.

Grazing in wet conditions

Poor ground conditions may be a challenge on many farms but the opportunity to improve margins should not be ignored. Turnout may also be necessary on some farms due to low silage stocks. There are several extended grazing techniques that can help:

  • Start by turning out cows for just a few hours each day, bringing them back in before they start to roam and cause poaching.
  • Turn cows out in smaller batches to limit poaching, for example only turn out cows that are producing less than 30 litres and are confirmed in calf.
  • Graze drier fields when the weather is most challenging and if possible use different entrance/exit points for paddocks.
  • As ground conditions allow, gradually increase the number of cows going to grass.

Use a sulphur containing fertiliser

When ordering fertiliser, consider purchasing one that contains sulphur. Sulphur plays a major role in increasing N use efficiency, grass N uptake and subsequently grass yield, with research showing up to 2.5 tonnes per hectare yield response. It also helps reduce nitrate leaching. For grazing fields, apply 20 kg sulphur per hectare per year, ideally between now and the end of June. For silage fields, apply 15 kg per hectare per cut but if receiving slurry this can be reduced to 7 kg per hectare.

Sward rejuvenation - is white clover an option?

Grass seed mixes often contain 1-2 kg of clover seed, but management practices such as heavy fertiliser use and spraying docks does not generally allow it to persist. Clover does however have benefits including:

  • Reduced requirement for nitrogen
  • Increased feeding value
  • Increased animal intakes and performance
  • Environmental value

In open weed free swards where the soil pH is 6.3 or more and the P and K status is at least 2+ stitching in clover without the need for a full reseed may be an option. Nitrogen fixation by clover is proven to be the equivalent of up to 120 kg N per hectare of chemical fertiliser. By replacing chemical fertiliser, clover is a simple cost effective means to reduce the carbon footprint of milk production. Overseeding with clover is best done in April to give the clover time to establish but requires grass to be grazed tightly beforehand (less than 1,500 kg DM per hectare). Apply granulated lime and P/K fertiliser to help establishment, broadcast or slit-seed the clover seed at a rate of 2.5 kg per acre and roll the seedbed to ensure soil seed contact and improve the germination rate. Where there is a heavy weed burden, autumn reseeds with the sward killed off beforehand are generally more successful. Reseeding these with grass in the autumn and stitching in the clover the following spring is effective.

Fertiliser for first cut silage

The nutrient requirement for intensively managed grass swards for first cut silage is 120 kg N per hectare or 96 units per acre. 3,000 gallons per acre of slurry will supply 27 units with a further maximum of 69 units of fertiliser N required per acre. Unless the slurry has been analysed, assume it also supplies 32 units P and 59 units K. Soil analysis results should be used to precisely calculate fertiliser requirements. If you do not have results, assume that the 3,000 gallons per acre is supplying all the P and K requirements. Only apply a straight nitrogen plus sulphur fertiliser.

Derogated farms

It is a requirement for all farmers who have applied for derogation to complete a Fertilisation Plan. This is essentially a Nutrient Management Plan giving details of planned livestock numbers with estimates of the amounts of manure N and P produced and amount of organic manure likely to be imported or exported. It also requires details of the area of crops grown in each field, including grassland, crop nutrient requirements based on soil analyses and the likely amount of slurry/manure and chemical fertiliser to be applied. Details are also required on the capacity of tanks, lagoons and middens for the storage of slurry and manure.

Beef and Sheep

Prepared by: Jack Friar

Mineral supplementation for cattle at grass

Mineral supplementation should be considered at grass for both suckler cows and beef cattle. Research has shown that mineral deficiency is a widespread problem in soils across Northern Ireland.

Of particular concern is selenium and iodine deficiency, especially for suckler cow fertility. Trace elements play a key role in ovulation, conception and embryo survival. However, it is important to note that while mineral deficiency can limit fertility, if overall nutritional needs are not met, fertility will still be compromised.

Mineral supplementation should also be considered for beef cattle that are not receiving concentrates at grass. As many essential trace elements are involved in energy metabolism a deficiency will negatively affect feed conversion. If mineral levels in grazed grass are less than animal requirements cattle may not grow to their potential.

The ideal way to identify a deficiency is to get a pooled blood sample from a group of untreated animals analysed. Your vet can take the sample and get it analysed. If a deficiency is identified, there are various options available for supplementation including boluses, lick buckets and slow release tablets which are added to the drinking water.

Sheep parasite awareness and management

April usually coincides with the emergence of two parasites, nematodirus and coccidiosis, that affect lambs five to six weeks of age that are starting to eat grass. Infections due to these parasites can be confused with each other as they both cause scour in young lambs and severely affect performance. Treatment programmes are different and it is important to identify the cause at the earliest opportunity. This can be done by taking dung samples to your vet for analysis. Consultation with your vet is essential for correct diagnosis and to ensure the right treatment programme is implemented on your farm. Treatment for nematodirus is usually a white drench (benzimidazole type drench), whilst a coccidiostat oral drench or medicated feed for lambs that are being creep fed is normally used for coccidiosis. The medication for the creep feed can be fed either for prevention or control, but a prescription from your vet is required before your meal supplier adds it at the correct rate to your concentrate ration. Contact your local veterinary surgeon to ensure the prevention and/or treatment strategy best suited to your circumstances is chosen and followed correctly.

Keep an eye on early spring lamb weights

Lambs born in late December and early January may be ready to go to the factory in the next few weeks if they have had access to high quality grass and especially if they were offered creep feed. Most processing plants in Northern Ireland specify carcase weights of between 19 kg and 21 kg for spring born lambs. Ideally, lambs should have a fat score between 2 and 3, a carcase grade of R or U and are farm quality assured. To maximise farm profits, it is important that lambs are weighed regularly and drafted as soon as they are fit.

Closing off silage ground now

If your aim is to make high quality silage from your first cut this year, ground identified for silage should be closed off during the first week of April with the aim of cutting in mid-May. Later closing pushes the harvest date further into June when most grass varieties will have passed peak heading dates resulting in a decreasing D-value and overall quality. Making the highest quality silage possible helps ensure good daily liveweight gains and reduces the amount of concentrate inputs for finishing cattle or for feeding in-lamb ewes next winter. Apply slurry and fertiliser to closed off ground based on soil analysis results. For example, land with optimum indices of 2+ and 2- for phosphorus (P) and potassium (K), apply up to 120, 40 and 80 kg per hectare of nitrogen (N), P and K respectively from organic and inorganic sources, in addition to 35-40 kg per hectare of sulphur.


Prepared by: Leigh McClean


Winter cereals

Weather conditions permitting, aim to apply the second N dressing by early stem extension. Inspect crops for recently emerged broad leaved weeds and apply top-up herbicide as temperatures warm up. Observe product labels for latest application timings, sequences with other herbicides and approved tank mixes with other products.

Disease control

In winter barley, T1 timing aims to maintain tiller numbers. In thinner or later drilled crops, disease pressure should be lower than early drilled thicker crops, so match fungicide rate to yield potential and the level of disease present. For best control of the main yield robbing barley diseases, rhynchosporium, net blotch and ramularia, use a mix of active ingredients rather than single active ingredients. Consult your BASIS registered agronomist for advice on effective product combinations and application rates. Ramularia is difficult to manage particularly in crops under stress. Teagasc trials on ramularia show both prothioconazole and mefentrifluconazole perform consistently better than other leading actives when applied protectantly.

In winter wheat, protecting leaf 3 at T1 (GS32-33) and flag leaf at T2 (GS39) are key spray timings for controlling Septoria. Mixtures containing actives mefentrifluconazole (Revysol) or fenpicoxamid (Inatreq) give highest levels of activity but at a cost which is best justified at T2 and where disease pressure is high. AHDB trials on yellow rust show benzovindiflupyr and prothioconazole (Elatus Era) are particularly effective, but all good mixtures perform well. Folpet should be included as a partner in mixes to protect other fungicide groups as its inclusion slows the pace of disease resistance developing in both wheat and barley.

Spring crops

As we move through April, gradually increase seed rate up to 400 seeds per square metrefor spring barley. Plan to treat weeds in all sown crops as soon as possible. Pre-emergence herbicides in spring cereals can help manage resistant broad leaved weeds such as chickweed and target problem annual meadow grass. Check with your agronomist as some of the Extensions of authorisation for minor use (EAMUs) have not been renewed and fewer options are available than was the case in previous seasons.

The Protein Crop Scheme continues for 2024. Once planted, protein crops grow and develop quite slowly for the first few weeks after emergence. This means weed control is the most important thing you can do to ensure a good yield in peas and bean crops. Pre-emergence herbicide application gives the best control of broad leaved weeds as post-emergent options are limited, do not cover a wide spectrum of weeds and can be harsh on the growing crop. If grass weeds or cereal volunteers appear a graminicide (herbicide specifically targeting grass and cereals) can be applied. The optimum graminicide timing is usually when most grass weeds have emerged, before the crop canopy closes in and before the latest safe application which varies depending on crop growth stage and the product used. Consult the product label and get agronomist advice if you are unsure of timing to avoid crop damage.


Sprouting and chitting

Pre-sprouting systems must ensure adequate temperature, ventilation and light to control sprout growth and protect against frost. As seed planted now will be for the main crop ensure that the pre-sprouting system encourages multiple sprouting to produce many tubers which can increase in size over a longer growing season than with early varieties.

Weed control

A range of pre-emergence products offer good weed control, though for best results these need to be applied as soon as possible after planting. If the window for pre-emergence herbicides has passed, contact herbicides such as carfentrazone (Shark) are an option.

As distant as it seems at this time of year, consider how late plantings could delay harvest. If planting is delayed, a rule of thumb is to reduce the N rate by 1.0 kg per hectare per day after planned planting date and avoid late applications which keep the canopy greener for longer, holding back the start of harvest at the other end of the season.


Prepared by: Liz Donnelly

Pig Regen health survey

The Pig Regen health survey, which is carried out by a vet examining pig carcases three times per year, provides a 'snapshot' of the health status of your herd. It gives information on the level and severity of enzootic pneumonia and pleurisy, the percentage of pigs with pericarditis, mange and tail biting lesions and the percentage of livers with milk spot. During February, over 15,000 pigs from 149 units were examined for the presence of lesions and other health problems.

The results, which are colour coded to reflect the severity of potential health problems, were sent to you recently by Pig Regen. If you have not studied the results yet, please take time to read them as the information provided is very valuable and could help explain problems on the farm. If you are not sure about the figures and comments made on the report, contact your vet for advice.

The recent survey shows a continuing and disappointing increase in the percentage of livers with milk spot. Milk spot, which is caused by the roundworm Acarius suum, is of concern as pigs infected with worms have a poorer feed efficiency, higher feed usage and lower growth rate. Experimental infections have shown reductions of 2-10% in growth rate and 5-13% in feed efficiency. Almost 60% of batches of pigs checked during February were affected by milk spot. In other words, 88 of the 149 batches examined had milk spot. In the latest survey overall 15% of livers were affected, a1% increase from the September/October 2023 survey.

However, worm control is difficult due to the sticky nature of the eggs which means they can survive on pen floors and block walls to a height of approximately 1.5 m for up to five years. On farms where milk spot is a continuous problem, thorough cleaning of farrowing and finishing accommodation with detergent or hot washing soda, combined with monthly anthelmintic treatment of the breeding herd, is critical. Pigs in the feeding herd should also be treated every six weeks with an anthelmintic. Thorough drying of washed pens may also be of value as pressure washing without drying can increase the survival rate of worms. Your vet will provide you with more details on a control programme that is applicable to your farm.

Pig farm security

In previous management notes I have written about the importance of biosecurity. Good biosecurity involves taking steps to secure your farm against the entry and spread of disease. This note is a reminder of another type of security that is equally as important, site security against intruders.

To improve site security:

  • Check the condition of all boundaries. Are there are any holes/gaps that need to be made secure?
  • Restrict the number of entry points to the farm. Hang a security gate at the main entry point.
  • Ensure all gates are securely hung and locked with heavy duty chains and padlocks.
  • Lock as many pig house doors as is possible. Use key alike padlocks where one key locks all the padlocks on the farm.
  • Put up clear signage indicating entry is not allowed and trespassers will be prosecuted. If a farm does not have signs at the main entry, the police will treat an incursion as trespass which is a civil offence as opposed to aggravated trespass which is a criminal offence.
  • Consider installing security lighting such as movement activated lights, CCTV or infra-red/laser technology and position at vulnerable points.

Notes to editors:

  1. Follow us on X and Facebook.
  2. All media queries should be directed to the DAERA Press Office: [email protected] or telephone: 028 9016 3460.

Share this page