Management Notes for September 2020

Date published: 04 September 2020

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, Environment and Rural Affairs (DAERA).

If ground conditions allow, autumn is a great time to apply lime.


Prepared by: Christopher Breen

Managing grazing in September

Concentrates account for about two thirds of the variable production costs of milk. Making the most of grazing will reduce your costs. Good conditions, quality swards and the availability of after-grass means your herd has the opportunity to graze quality grass and potentially produce around 10 litres of milk from forage in September.

Planning for early grass next spring

Building up covers for next spring is not an option for everyone. If you are planning an early turnout, this will be the last round for many paddocks. Actions you take now will have an effect on any early grazing next spring. The timing of paddock closure and residual grazing heights now, determines the start date for grazing and grass quality for your herd next year.

To allow early grazing the following points should be noted:

  • Paddocks closed now will be the first to be grazed in spring.
  • Graze paddocks to 5 cm or less on a rotational basis and close for the winter.
  • Paddocks should not be grazed again, even if there is good grass growth in October/November.

Colostrum for calves

Colostrum management is the single most important factor in determining calf survival and subsequent health. Calves are born without any immunity and rely on the protective effect of the antibodies derived from their mother's colostrum. The first colostrum feed should be a minimum of three litres or 10% of body weight, followed by a similar sized feed 12 hours later. Calves must also receive the first colostrum feed as quickly as possible after birth, at least within two hours. If the calf does not suck quickly, carry out stomach tubing to ensure the calf is properly protected. Good quality colostrum is also important and should have immunoglobulin (IgG) levels above 50 g per litre.

Colostrum quality can be measured easily on farm using a refractometer or colostrometer. For example, when using a refractometer a Brix value of greater than or equal to 22% indicates good quality colostrum. Dry periods of less than eight weeks, the number of calves a cow has had, vaccinations, calving season and how soon after calving the colostrum is suckled/milked from the dam for feeding can all have a significant effect on quality. A high level of bacteria in the colostrum, largely caused by inadequate hygiene, management and storage can reduce the absorption of IgG. This results in the failure of passive transfer of antibodies from the colostrum to the calf.

Following harvest of colostrum, the recommendation is to keep it in a refrigerated environment for up to 48 hours, if not being fed directly to the calf. If you are not sure of colostrum quality and if feeding and management are providing your calves with enough protective immunity, get your vet to carry out ZST tests on blood samples from healthy calves at two to six days old.

September jobs checklist

  • Correct soil pH where necessary. If ground conditions allow, autumn is a great time to apply lime. Aim for a pH of 6.3 to get the optimum results from fertiliser next year.
  • Carry out vaccinations due well in advance of the breeding season.
  • If conditions allow, subsoil compacted areas and let them rest over the winter period.
  • 15th September is the last day for sowing chemical nitrogen and phosphorus fertiliser on grassland.

Download more information and guidance during the Covid-19 pandemic.


Prepared by: Nigel Gould


Lambs - sell or finish?

With store lamb prices relatively positive this year to date, the decision needs to be made whether lambs still on the farm should be sold now or kept for finishing. Do a budget, allowing for the cost of bringing them through to finish and the expected value of finished lambs, with the latter often difficult to estimate. Look at market trends in recent years. Some of you may choose to store lighter lambs over the winter to take advantage of the typical price rise which occurs when lamb supplies become tight. However, be careful not to reduce grass supplies to an extent which will affect the main ewe flock. If surplus grass is available, which may be the case this year where cattle were housed earlier, finishing off grass may be a viable option. Lambs can gain 80-130 g per day at grass. However, performance is linked to lamb type, sward quality, parasite control and the absence of prolonged periods of wet weather. Creep feed will reduce the time to slaughter, but will incur a higher cost. The other alternative is to house lambs and intensively finish indoors. Performance is increased and feed conversion can be 7-8 kg of concentrate to 1.0 kg of live weight gain, depending on ration quality and lamb type. A source of roughage in the diet is important for rumen function. Allow a total dry matter intake of 4%. Lambs can consume 1.5 kg of concentrate in an ad-lib system and have the potential to gain up to 250 g per day during the finishing period, however large variation will still occur between lambs. Avoid feeding ewe minerals to lambs due to the risk of urinary calculi in ram and wether lambs. Also, take into account veterinary costs and mortality. 

Preparing ewes for breeding

If vaccinating ewes for Enzootic abortion or Toxoplasmosis, this needs to be done at least four weeks before introducing the rams. All other veterinary treatments and administration of mineral boluses should be carried out two to three weeks before introducing the rams. Ideal ewe body condition score at breeding is 3.0 to 3.5 for lowland ewes and 2.5 to 3.0 for hill ewes. Rams should have a body condition score of 4.0 before breeding. Disturb ewes as little as possible during the breeding period.

Quarantine purchased sheep

If buying in replacements try to minimise the chance of importing problems. Have a good quarantine strategy in place, particularly in relation to removing any resistant worms and scab. On arrival, keep sheep away from the rest of the flock. Contact your vet about suitable worm and scab control methods. Ideally, house them for

24-48 hours and keep them separate from the existing flock for at least three weeks. The perceived hassle will be well worth the effort if it avoids the introduction of health issues such as lameness and scab or worms resistant to any of the main classes of wormers.


Scanning spring calvers

Scan spring calving cows and heifers now to identify empty animals which can be culled early. Early scanning (from 35 days after bull removal) will give a more accurate timing of pregnancy which will be useful during the busy calving period next spring. Consider early weaning and/or introducing supplementary feed to allow these cows to be slaughtered or sold before the winter housing period. In addition to savings on winter feed, these cows may be sold before the traditional flow of cull cows onto the market after the main weaning period.

Autumn calving cows

On many farms autumn calving will now be well under way. Close observation is needed both pre and post calving. Large calf size can sometimes be associated with autumn calving, particularly where grass has been plentiful and assistance may be required. Grass tetany, caused by magnesium deficiency can sometimes be a problem in autumn calving herds, particularly where there are stress triggers such as changeable weather or prolonged wet periods. The most popular preventative measures include magnesium lick buckets and boluses.


Managing swards in autumn

Nitrogen fertiliser can still be applied up to 15th September if weather and ground conditions allow. Apply 40 kg nitrogen per hectare (30 units per acre) to younger swards and drier areas to provide extended grazing for young cattle and sheep. At the start of September ideally there should be 30 grazing days of grass ahead. If ground conditions deteriorate on heavier soils, avoid poaching by housing cows and forward store cattle. Move stock quickly over the grazing blocks, ideally every one to three days, to avoid poaching in wet periods and allow swards to recover.


Prepared by: Pamela Gardiner

During Covid-19 restrictions, CAFRE continued to deliver knowledge transfer and advice using a range of online technologies such as Teams, Webex and Zoom. Staff virtually met many Business Development Group members, held conference style events such as Sustainable Cow Production and Virtual Farm Walks. These have proved to be a good alternative to face-to-face training events as hundreds of attendees were able to access the online meetings and events without the need to leave the comfort of their home. It also reduced the amount of time away from the business. The larger online events have been recorded and are available to view at a convenient time via the CAFRE website.

These online technologies enable attendees to view video feeds, presentations, text chat, ask questions, view answers and take part in polls. This month’s management note includes some tips to help you get the most out of your online meeting or event, irrespective of which platform you use.

Complete a broadband speed test

To get the most from your online meeting/event (audio and video), you will need suitable internet speed. A broadband speed of 2Mbps download and 1Mbps upload is recommended. This speed must be consistent and reliable for the duration of your online meeting/event.

A speed test helps you see what download and upload speed you are getting. There are many websites and apps available to help you do a speed test such as and the Speedtest by Ookla app.

If you are below the recommended speed, contact your broadband supplier and discuss with them the possibility of improving your service. If suitable fixed line broadband is not available in your area, an alternative may be 4G mobile data services. Check with the mobile phone providers for coverage in your area. Other broadband technologies such as satellite or wireless can provide these recommended speeds, but costs and availability will vary depending on specification and location. Attending online meetings will use significant amounts of data, so may not be suitable if you are on a data limited contract.

Joining an online meeting/event

You can join an online meeting/event from your computer or mobile device. It is a good idea to join early to make sure you are set up and ready to go for the start of the meeting/event. You will normally receive an email invite with joining instructions and/or a link. If it is your first time joining an online meeting/event, when you click on ‘join’, the platform will prompt you to download the appropriate app to let you connect to the meeting and future meetings/events. Often, you will be given options of how you want to hear the audio and whether you want to show your video or not. It is advisable when attending online meetings/events to keep your audio muted until you wish to speak (some meeting/event organisers will automatically mute attendees to avoid distracting background noise).

Participating in an online meeting/event

During the online meeting/event you can listen and view content shared by the presenters. Depending on how the organiser has set up the meeting/event you may be able to electronically ‘raise your hand’ to ask a question, submit a written question, participate in polls, text chat and provide feedback through surveys.

Troubleshooting during an online meeting/event

If you find during the online meeting/event you have poor audio/video quality, consider using wired connections rather than wireless to connect your computer/laptop directly to your broadband router. Using wired headphones/microphone rather than the built in speaker/microphone will make your voice sound better to others in the meeting. If you are struggling with poor video and audio try switching off your own video feed or switch off incoming video feeds from other attendees. Alternatively, if the online platform offers a dial in facility you can participate in the meeting using your phone by dialing the meeting phone number provided on the invite.

Visit the CAFRE website, DiscoverCAFRE Facebook or Twitter sites and the farming press to find out about upcoming CAFRE online events.


Prepared by: Leigh McClean


Variety selection

The starting point for effective disease control to achieve high yielding crops is variety selection. Consider varieties with good disease resistance scores and favourable agronomic profiles as part of an integrated pest management strategy.

Unfortunately due to COVID-19 the annual variety trial tours could not take place this year. You can however view the AHDB funded trail plots at AFBI Crossnacreevy with Dr Lisa Black by visiting You Tube for winter barley and winter wheat.

Aphid monitoring and virus control

Good planning is essential to reduce the risk from BYDV transmitting aphids in an era without insecticide seed treatment and pyrethroid resistance in aphid populations.

Cultural control of weedy stubbles and volunteers by destroying the ‘green bridge’ for wingless aphids is achieved by burning off seven to ten days before ploughing or allowing 14 days between ploughing and sowing. 

Infection by migrating winged aphids is the most common route for BYDV infection in autumn cereals. To assess this threat AFBI, using a suction trap, monitor cereal aphid migration. Aphid migration is updated weekly, along with advice on control, and is available from the AFBI website. Historically data shows, as the season progresses, aphid migration and consequent BYDV infection pressure diminishes. Therefore, early drilled autumn crops are at greater risk and growers should balance this risk against later sowing, slower emergence and potentially poorer establishment. Concerns about pyrethroid resistance means you only apply pyrethroid sprays when aphid colonies, not individual aphids, are present on leaves.  

A few winter barley varieties show tolerance to BYDV. This means they can be infected without displaying symptoms and suffer less of a yield penalty in severe outbreaks than non-tolerant varieties. Small quantities of tolerant seed are available this autumn so consider these for early sown high risk situations.    

Cultural weed control

This year’s prolonged dry and wet spells have caused a flush of weeds in more open crops. Stale seedbeds are a useful way of reducing the weed seed bank. Lightly cultivate immediately after harvest to encourage a flush of weeds which can be burnt off before ploughing and drilling. 

Slug monitoring

Now is the time of year to assess slug numbers before winter crops are sown. Set traps on damp soil using dry bait under a tea tray sized cover, leave overnight and check for slugs the next day. Removing green cover reduces their habitat and feed source. A clod free, firm seedbed allows seed to germinate quickly whilst restricting slug movement, making it harder for them to find seed and seedlings. If slug numbers exceed four per trap in cereals or one per trap in oilseed rape consider applying ferric phosphate slug pellets if emerging crops are still at risk. 


Late season management

Maintain blight spray programmes until after haulm desiccation to avoid late blight developing. Blight strains insensitive to Fluazinam are common in Northern Ireland meaning this active should no longer be relied on for tuber blight control. The EuroBlight late blight fungicide table provides alternatives to Fluazinam which have high tuber blight ratings and good antisporulant activity.


Regular trial digs indicate when tuber size has reached market specification, allowing desiccation to be timed accordingly. Without Diquat growers have PPO Inhibitors, Spotlight Plus (carfentrazone) and Gozai (pyraflufen-ethyl) as desiccation spray options. These can take longer to give the same effect as Diquat so plan to make the first application seven to ten days earlier than usual. They work best in bright, sunny conditions. Good spray penetration into the canopy is key so use slow forward speeds, high water volumes with forward and backward facing nozzles applying a medium quality spray. Both products are compatible with the fungicide Ranman Top, which can improve the desiccants efficacy whilst also having good activity on tuber blight.

Store and equipment preparation

Spores of many storage diseases lie dormant in the dust and debris remaining in stores, boxes and equipment. Thorough cleaning and disinfection is one of the most effective ways to avoid carryover of disease from previous years. Significant reductions in infection can be achieved by thoroughly power hosing or vacuuming stores and equipment before the new crop is harvested. 

Notes to editors: 

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  2. All media queries should be directed to the DAERA Press Office.

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