Management notes for May 2016

Date published: 04 May 2016

Management Notes are prepared by staff from the College of Agriculture, Food and Rural Enterprise (CAFRE). Questions and comments are welcome to allow CAFRE to address the issues that are important to you. Please contact the author directly. CAFRE is a college within the Department of Agriculture and Rural Development (DARD).

DARD news


Prepared by Michael Garvey
telephone: 028 3752 9054                                            

Silage – when to cut

Aim for a D value of 67-70. This year in most areas, this corresponds to a cutting date in early/mid May. A bright day is ideal for cutting as the sun increases the sugar content of the grass giving a better fermentation. Sunshine also promotes a more rapid wilt, reducing the amount of water ensiled. Mow grass dry as wet grass results in a longer wilt time and a reduction in nutrients. Also mowing grass later in the day is more preferable than starting at 9am when dew may still be on the grass.

Wilting grass

  • to speed up the wilting process spread the cut crop over the entire field immediately after mowing
  • aim for a target grass dry matter (DM) of 30% at harvesting
  • a rapid wilt prevents excessive sugar and protein losses
  • in ideal wilting weather, a crop if spread out, will be ready to lift within eight hours


  • ideal chop length promotes good consolidation in the clamp and provides enough fibre for the cow to ruminate
  • set chop length at 25 mm for grass with a DM of 30%
  • if grass is wetter (less than 20% DM) consider a longer chop length of 50 mm

Clamp management

The purpose of ensiling grass is to preserve and minimise the loss of nutrients therefore improving feeding value. Silage fermentation can be divided into two phases:

Phase 1 - chopping grass to the correct length, ensiling at the recommended dry matter, filling the silo quickly and distributing grass evenly in the silo can eliminate oxygen at this stage.

Phase 2 - micro-organisms in the grass produce lactic acid which is the primary acid responsible for lowering the pH in grass, producing silage and making it stable. Undesirable micro-organisms can dominate if the pH does not drop rapidly.

The key to making good silage is to remove the air and make the clamp as air tight as possible. Ensure the ensiled grass is spread in shallow layers and rolled continuously and always cover the silo at night. At the end of harvest apply an effective cover and weight the cover, paying particular attention at the shoulders of the pit.

Can an additive help?

Effective silage fermentation produces high levels of lactic acid reducing the crop pH. Silage additives can aid this process. A variety of additives are available - bacterial inoculants, enzymes, non-protein nitrogen sources, acids and sugar sources. It is important to emphasise that none of these products are a substitute for good silage making techniques and management but they should help make a good situation better.

Fertiliser for second cut

The phosphate (P) and potash (K) recommendations for second cut silage vary according to soil reserves. Do you have recent soil analysis results for your silage fields? If so, use the online CAFRE Crop Nutrient Recommendation Calculator to work out your slurry and fertiliser requirements for second cut silage.

As a guide, at soil index 2 for P and index 1 for K, typical of fields normally cut for silage, slurry has the potential to provide some of the nitrogen (N) and K and all the P needed. At a practical level a 22,000 litre application of dairy cow slurry per hectare (2,000 gallons per acre) applied by tanker and trailing shoe, contains 17 kg of N, 26 kg of P and 63 kg of K. Top-up with 375 kg per hectare of a 22:0:10 type fertiliser (3 cwt bags per acre) to meet second cut needs.

Results from AFBI research highlights the importance of sulphur for improving grass production and the majority of second cut silage swards will give a positive response to applying fertiliser containing sulphur.

Evenly spread slurry will improve silage fermentation and minimise sward damage.

Beef and sheep

Prepared by Darryl Boyd
telephone: 028 9034 0957



Coccidiosis may be a problem on sheep farms. The poor weather in April prolonged housing for ewes and lambs, with contaminated bedding increasing the risk of spread. Sheep outdoors may also be at risk as supplementary feeding also increases the risk of spread as sheep congregate around troughs.

Take action quickly if cases are identified as treatment often has a preventative element. Physical steps should also be taken to prevent spread to other lambs, for example move troughs regularly to the driest areas in fields.


Nematodirus is also quite common in May and the risk increases with a sharp rise in temperature. Lambs over six weeks of age, which are beginning to graze more grass are most at risk. Poor milk levels, associated with difficult grazing, may also place more pressure on younger lambs to graze and therefore increase the risk. Although some resistance has been identified, for most farms, a white (1-BZ) drench is effective against Nematodirus. It may be necessary to treat lambs more than once depending on weather conditions and spread of lamb ages within a treated group. It is therefore good practice to keep lambs in tight age groups.  

Sustainable Control of Parasites in Sheep (SCOPS)

Nematodirus can strike very quickly and at different times throughout the United Kingdom. SCOPS, an industry led group, forecasts hatches for certain areas. Use these forecasts, in combination with your grazing history, to assess the risk of Nematodirus infection in your lambs. Up to date forecasts in local areas are available at:


To manage/utilise grass growth it is important to try and match stocking rates to growth. Daily dry matter (DM) intake is 3.5% of bodyweight. The DM intake for 80 kg bodyweight is 2.8 kg (80 x 3.5%). Divide the daily grass growth figure by the intake figure to estimate a suitable stocking rate.


Suckler cows

Cattle will hopefully be at grass on a rising plane of nutrition. Spring calving cows should be body condition score 2 at mating. Condition scoring cows and replacement heifers before the breeding season allows preferential treatment to be given where necessary, but ideally this should have been managed through the winter. As discussed last month a major concern after turnout is Grass Tetany. Mineral supplementation is also important in the breeding season.

Nigel Gould, Beef Technologist at CAFRE, Greenmount says: “Consider mineral supplementation at pasture as soil tests across Northern Ireland suggest soil mineral deficiency is a widespread problem, especially selenium and iodine. Selenium and iodine are important to breeding animals as they influence fertility. Iodine deficiency results in the birth of weak calves lacking vigour. Also think about copper and cobalt as both are linked to poor thrive.

Before supplementation analyse a pooled blood sample from a group of animals. This will inform you which minerals need to be supplemented on your farm. Forage samples can also be analysed to determine the mineral content of the diet. The type of supplementation depends on cost and convenience.”

Common methods of supplementation

  • Bolus - provides slow-release mineral supplementation over a period of time, usually five to six months. Exercise caution when depending on this method for iodine supplementation for the second half of the stated period
  • drinking water - mineral tablets dissolve slowly in the water trough and are replaced weekly. This is a popular method of supplementing iodine
  • oral drench - a relatively inexpensive method, however regular supplementation, every two to three weeks, is required. The need for good handling facilities for both animal and farmer Health and Safety is therefore important
  • topical treatment - involves applying pour-on to the hide of the animal, usually applied to the back or flank. This is a useful method of iodine supplementation, however regular treatments, every two to three weeks, are required. Again handling facilities must be suitable
  • in feed - this is often the cheapest and most convenient method of mineral supplementation but only if concentrates are being offered at grass


Prepared by Liz Donnelly
telephone: 028 9442 6767

Meeting the bank manager

Times are tough in the pig industry -  there is no doubt about that. Pig prices remain stubbornly low, with over production, poor demand and the loss of the Russian market the main causes. If you find yourself in the situation where you need to talk to the bank my advice is to contact the manager as soon as possible. Burying your head in the sand and ignoring things will not help the situation. If you are meeting the manager follow the motto of the Scouts ‘Be prepared’. Know your business inside out from both a performance and financial point of view. Calculate your total debt including bank, merchant credit and any other unpaid bills. Familiarise yourself with your performance figures and bring up to date figures and accounts with you. Obtain information that will help you explain the current pig industry situation to the manager and what is likely to happen to pig and feed prices over the next six to 12 months. It is up to you to sell yourself and your business as a sound financial investment. There are financial options available to help you through the current situation. These include:

  • increasing your overdraft facility
  • reverting to interest only payments for a short time
  • extending existing loan periods to reduce payments
  • combining loans to give a single payment

The sooner you talk to the bank manager the more options there are to resolve financial problems.


Kennels, either purpose built or as part of a house conversion, are quite popular on local pig units. The purpose of a kennel is to provide a lying area for the pigs that is warmer than the feeding/dunging area. I recently checked the temperature of a kennelled lying area in a weaner house using temperature recording data loggers. The loggers record temperature every few minutes for a period of time. The data is then downloaded onto a computer and a graph shows the actual temperature over the time period. For this house there was virtually no difference between the temperature in the kennel and feeding/dunging area. The reason for this is that there is no lip on the kennel lid and the lid is not insulated. The lack of lip and insulation means the warm air escapes through the lid and is not retained within the kennel. The moral of this story is that both insulation and a lip are required to achieve a higher temperature in the kennelled lying and area compared to the dunging/feeding area.

Something of interest!

As you know concrete pig slats have to meet EU regulations for gap and beam width. The maximum gap size and minimum beam width depends on the stage of pig, for example, the maximum gap for finishing pigs, allowing for a 3 mm tolerance is 21 mm and the minimum beam width, again allowing for a 3 mm tolerance, is 77 mm. You can find details of the gap and beam widths for other stages of pigs in the Essential Pig Data Handbook which was posted out to all producers last year. If you did not get a copy of this booklet, which contains key figures and measurements, please get in touch.

Some slats in older pig houses do not meet the requirements as the beam width is too narrow. Plastic and stainless steel inserts are available which both increase the width of the beam and reduce gap size. After measuring the beam width of slats in an older partly slatted finishing house a local producer realised the slats were too narrow. To solve the problem he purchased plastic inserts which he used to successfully increase the beam width   (see photograph). Also importantly to date the pigs have not removed any of the inserts. The inserts can also be used to repair worn slats around feeders.


Prepared by Leigh McClean
telephone: 028 9442 6928

Winter cereals


The majority of nitrogen (N) should be applied to winter barley by now. However some crops, particularly six row varieties on continual arable soils, may benefit from a late top-up at flag leaf of 30-40 kg per hectare. Apply any remaining N to wheat by flag leaf emergence. 

Winter barley disease control

Winter barley is now progressing through stem extension after yet another late start to spring.  As a result of slow early crop growth and development many T1 sprays were only applied towards the end of April. Aim to apply T2 sprays within four weeks of T1, ideally when the flag leaf and the first few awns have emerged. Weather permitting, maintaining the four week gap should be achievable this year due to the late start to the fungicide programme. The best performing fungicide choices combine a triazole and SDHI mixture for example, Siltra, Adexar and Bontima. See the DARD Combinable Crops webpage for links to HGCA fungicide decision support charts (

Winter wheat and SDHI resistance

Similar to winter barley, wheat crops got off to a slow start and as a result are likely to have received their T1 fungicide in the last days of April or early May. Prepare for a timely T2 treatment at flag leaf emergence no later than four weeks after the T1 spray. A well applied T2 spray gives a bigger yield response in wheat than any other spray timing.

A recent Teagasc survey has shown suspected SDHI resistance in septoria at low frequency across Ireland and a higher number of samples with reduced sensitivity to the SDHIs. Early research suggests all commercially available SDHIs will be affected although efficacy of the SDHIs, when used responsibly, is unlikely to be dramatically affected during the 2016 season. 

It is essential you use SDHIs responsibly as part of fungicide programmes which minimise potential selection for these resistant septoria strains. My advice to wheat growers is:

  • only use SDHIs where necessary
  • never apply more than twice in a season
  • always use in combination with a multisite protectant (for example Bravo or Phoenix) and a triazole fungicide

Spring cereals

In spring cereals herbicide resistance is an ever present issue. Options exist to apply residual herbicides more commonly used on winter cereals pre- or early post- emergence. These herbicides provide a different mode of action and improve annual meadow grass control. They are mostly extensions of minor use (EAMUs), details of which are on the DARD Combinable Crops webpage. 

If crops are too far forward for the residual option, aim to apply a mixture of at least two broad-spectrum herbicides whenever most of the weeds are at the two to four leaf stage. This will ensure weed competition is removed at an early stage of crop development and may allow product dose rates to be reduced.   

It is also good practice to prevent disease becoming established at this stage by tank-mixing a fungicide with your herbicide. As rhynchosporium is the most damaging disease in our current spring barley varieties, product choice should reflect this. Products previously mentioned for winter barley are equally effective on spring barley, although at a lower rate.

Nitrogen top dressing is best applied once tramlines are visible at the two to three leaf stage (GS 12 to 13). Later applications than this may green the crop but add little yield.


As planting progresses it is important to ensure good quality seed beds are produced. Providing good soil contact around the developing tuber helps reduce scab and also allows residual herbicides to work effectively. Also periodically check the correct planting depth and spacing are being achieved.

Put plans in place for early weed control to ensure key timings are not missed. Where pre-emergent products are used, crops should be checked regularly to ensure herbicides are applied on time to avoid crop damage. 

Notes to editors: 

  1. All media enquiries to DARD Press Office, or tel: 028 9052 4619.

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