Crops management notes
The Crops Management Notes author is Robin Bolton you can email him at robin.bolton@dardni.gov.uk
Management notes 2016
Latest management notes for 2016 are now available using the links below:
October 2015
Cereals
Monitoring crops in store
With the harvest rush hopefully now mostly past and the focus on establishing winter crops, grain in store is sometimes forgotten about during this busy autumn period. Continue monitoring stored grain to make sure small issues don’t develop into big problems down the line. Weekly monitoring is recommended until both grain moisture and temperature have stabilised. Pitfall or floor traps give an indication of the number of store insects and mites present. These store pests can multiply rapidly in heated grain, therefore early detection is the best way to prevent rising populations and grain spoilage.
Clearing rainwater guttering may have been part of the pre-harvest clean up. However chaff, leaves and straw can block gutters and cause leaks into stores so check and clean as necessary. Inspect rodent bait points regularly. Remove dead bodies and top-up bait boxes making sure they are safely out of reach of non-target animals or birds. Also record the inspection.
Slug monitoring
Slugs have been a constant companion on crop walks this year, no doubt fond of a cool damp summer devoid of prolonged dry periods. Where slugs have previously been a problem, numbers are likely to be high this autumn. Be vigilant, particularly where seedbeds are cloddy, damp and seedling emergence is slow, as damage is most severe under these conditions. Continue to monitor all winter crops until plants are beyond the vulnerable seedling stage. You should note that methiocarb based slug pellets are no longer authorised for use. If using metaldehyde slug pellets follow the metaldehyde stewardship guidelines. More details of treatment options are available on the DARD website (www.dardni.gov.uk). Follow the countryside and farming link to the combinable crops page.
Aphid monitoring and virus control
Controlling virus-carrying aphids is crucial to eliminating the cereal virus risk. After emergence, crops are still at risk from winged migrations of aphids throughout the autumn. These migrations are monitored by AFBI and populations are posted weekly on the combinable crops section of the DARD website, along with information on virus vector control through seed dressings and aphicide spray application.
Weed control
For troublesome grass weeds the most effective control is an integrated approach. Even if the window for using stale seedbeds has passed the opportunity still exists to apply pre or early post-emergence herbicides. This is especially important for winter barley as spring herbicide options are limited. Further details are available on the DARD website.
September 2015
Cereals
Planning for greening and new GAEC
The rules on greening which came into force last year will still apply for 2016. When planning autumn drilling it is important to consider cropping options to meet the crop diversification requirements and, where applicable, Ecological Focus Area requirements. Also new Good Agricultural Environmental Conditions (GAECs) come into force this year which prevent leaving soil ploughed over the winter period and also require stubble or a crop cover to be in place on the soil, unless weather conditions prevent the establishment of a crop cover. Full details of greening and the new GAECs are available on the DARD website.
Cultural weed control
Between harvest and drilling is a good time to establish stale seed beds as part of an integrated approach to weed control. Grass weeds, such as brome grasses, are increasing and are difficult to control, particularly in winter barley, due to more limited weed control options. Where sterile brome is the main problem establish the stale seed bed as soon as possible after harvesting. However, if meadow or rye brome is the main problem leave three to four weeks before establishing the stale seed bed.
Soil analysis
Following harvest is the best time to carry out soil testing. Soil analysis results and the DARD Crop Nutrient Calculator can be used to correctly calculate crop requirements within nitrate and phosphate regulations. Maintaining the correct soil pH is vital for the efficient use of fertilizer and good grain yields.
Pest and virus control
Place bait traps to assess slug numbers. Four or more slugs per trap indicate a risk of damage and slug pellets should be applied following the metaldehyde stewardship guidelines, or, if possible, use products containing ferric phosphate.
Controlling virus carrying aphids is crucial for eliminating the cereal virus risk. At particular risk are crops following grass and weedy stubbles. To avoid this destroy the ‘green bridge’ with glyphosate two weeks before sowing. After emergence crops are still at risk from winged migrations of aphids throughout the autumn. These migrations are monitored by AFBI and populations are posted weekly on the Combinable Crops section of the DARD website along with options for control.
Potatoes
Late season management
Regularly inspect crops to ensure blight does not establish as crops begin to senesce. Maintain blight spray programmes until after haulm desiccation. Regular trial digs should be carried out to indicate when tuber size has reached your market specification, allowing desiccation to be timed accordingly. Allow sufficient time for full skin set before harvesting the crop into a controlled environment store.
Store hygiene
Clean stores are essential for maintaining tuber health and quality post harvest. Spores of many storage diseases lie dormant in the dust and debris in stores, boxes and equipment. Significant reductions in infection can be achieved by thoroughly power hosing and vacuuming stores and equipment before the new crop is harvested and between batches of potatoes, particularly if there was any disease in the previous lot. Effectiveness can be further improved by applying an approved disinfectant after washing and vacuuming.
Reducing damage
Mechanical damage was a significant problem last year due to the very dry September and resulted in problems in store and the down-grading of produce. It is important to set machinery correctly and ensure all involved in harvesting and handling are aware of the importance of damage and bruise prevention. Damage can occur with drops from harvesters into boxes or trailers, bruising caused by insufficient soil on the web and crushing due to oversize tractor tyres running in the drill bottom.
Early identification of damage is critical and samples of the harvested crop should be taken daily, washed and inspected for surface damage and hot boxed to quickly reveal any bruising.
Drying and curing
Drying potatoes quickly after harvesting prevents the development of skin blemish diseases and soft rots. Drying within 48 hours using positive ventilation systems significantly reduces the development of diseases such as silver scurf. The curing period immediately after harvest is one of the most important storage phases. Maintaining the crop at 12 to 15 centigrade and 85 percent relative humidity for a period of about two weeks, often referred to as ‘dry curing’, allows wound healing to take place, whilst minimising the risk of disease development. Ventilating the store on dry afternoons during the curing period will normally provide adequate curing conditions.
May 2015
Winter cereals
Winter barley
Good growth in recent weeks means flag leaves have emerged on the majority of crops. Nitrogen should all be applied by this stage and attention turned to the T2 fungicide. The optimum T2 fungicide timing is when the flag leaf has fully emerged and the first few awns are appearing ensuring the gap between fungicide applications is not more than four weeks.
In cases where early drilled crops needed to be protected from the high carryover of winter disease with an earlier T1 and subsequent T2 there may be a benefit from a T3 spray, maintaining the three to four week interval after T2 fungicide. The best performing fungicide choices combine a triazole and SDHI mixture, for example, Siltra, Adexar, and Bontima. See the combinable crops page on the DARD website for links to HGCA fungicide decision support charts.
Winter wheat
As wheat crops will have received their T1 fungicide application by now, ensure plans are in place for a timely T2 application at flag leaf emergence. The T2 application to protect the flag leaf is the most important fungicide timing for wheat crops. As with barley, whilst growth stages are a good guide to spray timing, it is important to ensure the gap between the applications is less than four weeks.
In our high disease pressure climate triazoles continue to lose activity against septoria, and are most effective when used in a protectant situation as part of a mixture with an SDHI. SDHI containing products, Adexar, Aviator Xpro, Treoris and Seguris give better disease control than straight triazoles. Triazoles still have an important role protecting against other diseases and delaying septoria resistance developing to SDHI actives. Best practice is to apply a three way mix of triazole, SDHI and a multisite protectant, for example, Chlorothalonil or Folpet to maintain the future efficacy of the SDHI fungicide group.
Spring cereals
In spring cereals herbicide resistance is an ever present issue. Aim to apply a mixture of at least two broad-spectrum herbicides when most of the weeds are at the two to four leaf stage. This ensures weed competition is removed at an early stage of crop development, and may allow a reduction in product dose rates. Options exist to apply residual herbicides more commonly used on winter cereals to provide a different mode of action and improve annual meadow grass control. These are mostly extensions of minor use (EAMU’s), details of which are on the combinable crops page on the DARD website.
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, though at a lower rate.
Apply nitrogen top dressing once tramlines are visible at the two to three leaf stage (GS 12 to13). Later applications may green the crop but add little yield.
Leatherjackets can be a risk to newly established spring barley. Crops following grass or grassy stubbles are particularly at risk. Examine ten 30 cm lengths of drill at random throughout the crop. If ten or more leatherjackets are found from the 10 lengths of drill, an insecticide treatment containing chlorpyrifos is justified. When applying chlorpyrifos it is important to minimise drift. A current industry campaign requests everyone to use three star low drift nozzles and 20 m buffer zones when spraying this product.
April 2015
Greening under the new CAP regime
As planting progresses it is essential to check if your farm will have a greening requirement under the new CAP regime making sure you have made allowance to cope with it. Allow plenty of time to complete your Ecological Focus Area declaration as it requires a lot of detail. Greening represents approximately 30 per cent of your entitlement value so it is worth taking time to ensure it is correctly adhered to.
Cereal management
Winter cereals
Crops are progressing quickly and should all have received their first nitrogen (N) applications by now. If not already applied, winter barley crops and forward winter wheat crops, will require their main N applications as soon as possible (growth stage 30-32). Also aim to include sulphur at a rate of 25-40 kg per hectare of SO3. If organic manures have been applied these may have supplied some of this requirement and this should be taken into account. Any remaining potash requirement should also be applied now as N uptake is linked to potash availability. A shortage of potash can result in reduced N use efficiency.
Inspect winter crops for any broadleaved weed emergence since autumn or early spring herbicide application. If necessary apply top-up herbicide to any problem or late germinating weeds as soon as conditions allow. As with all pesticides adhere to product labels, paying particular attention to latest application timings, sequences with other herbicides and safe tank mixes with other products, all measures to avoid unnecessary crop damage.
Disease control
An ideal growing autumn and relatively good spring so far means good yield potential exists for many winter crops. However, the risk of disease is high and early sown crops already have high levels of disease on them. Most winter barley crops should have received their first T1 fungicide by now. If T0 or T1 has not been applied keep fungicide rates high to help get on top of infection in the crop. The next main spray is T2, which should be applied around growth stage 39. Fungicide options are similar to T1 sprays and again rates depend on disease levels at the time of spraying.
Some winter wheat crops will have received T0 sprays by now. If this has not been applied T1 will be critical to get on top of Septoria and should be applied around growth stage 32 or ideally leaf 3 emerging. For T1 use robust rates of Triazole, for example, Ignite or Proline mixed with an SDHI and multisite protectant. Links to HGCA fungicide decision support charts can be found on the crops page of the DARD website, along with growth stage charts to help plan your programmes.
Spring barley
As we are now past mid March yield potential is being lost through delayed drilling. Carry out sowing as soon as a good seedbed can be created. The chosen seed rate, calculated from the thousand-grain weight, should lie between 350 and 400 grains per square metre.
Monitor crops already sown for signs of slug and leatherjacket damage, particularly if emergence is delayed due to cold conditions. Make plans to treat weeds in emerging crops as soon as possible. Earlier treatment allows the use of a wider range of products helping manage resistant broad leaved weeds and also target annual meadow grass.
March 2015
Preparation for Greening
Crop growers face many challenges under the new CAP Basic Payment Scheme. It is important to assess the availability of Ecological Focus Areas to determine the need for any fallow before spring crop planting is completed. Also check cropping rotations and areas of crop grown comply with crop diversification requirements. A Greening Calculator, available on the DARD website, provides guidance on compliance. Mixed livestock and arable farmers should also check if any of the Greening derogations apply to their business.
Cereal management
Winter cereal
When field conditions allow winter crops should receive their first application of nitrogen (N) if this has not been applied already. Aim to apply one third of total N top dressing to winter crops during late tillering (by mid March for winter barley and mid to late March for winter wheat). Apply the remainder during early stem extension, Growth Stage (GS) 30-32, which, for winter barley is reached in early to mid April and for winter wheat in late April to early May. For crops on continual cropping rotations and where no organic manures have been applied withholding 30-40 kg per hectare of N until the flag leaf emerges at GS 37 may be beneficial. Apply remaining P and K requirements now based on soil analysis.
Most of Northern Ireland is now considered deficient in sulphur (S). Risk of deficiency is highest where soils are light and rainfall is low. Winter cereals should receive 20 kg S per hectare (50 kg SO3 per hectare) in the spring before GS 32. The most convenient application is as ammonium sulphate which also provides nitrogen. If potash is required sulphate of potash is also a good source.
Carry out remaining grass weed control on winter cereals as soon as possible and before annual meadow grass reaches tillering. Check product labels carefully for cut-off dates and growth stages.
Disease control
Some disease is already active in earlier sown crops of winter barley and these may benefit from a T0 application of fungicide to prevent too much pressure on the main T1 spray. Lush winter barley crops require a robust T1 spray in late March or early April at GS 30-31 to control rhyncosporium and mildew. Keep rates high particularly if a T0 has not been applied.
For winter wheat the main spray is a well timed T1 at GS 31-32 which is generally mid to late April. This should be based on a robust rate of triazole (Proline or Ignite) combined with an SDHI or mixtures. Links to HGCA fungicide decision support charts are available on the crops page of the DARD website, along with growth stage charts to help plan your programmes.
Drilling spring barley
Sowing should take place as soon as a good seedbed can be created. The chosen seed rate, calculated from the thousand-grain weight, should lie between 350 and 400 grains per square metre. The lower rate will suffice for March sown barley drilled into a good seedbed however in poorer conditions, or if sowing later, the higher rate is preferable. Monitor spring sown crops for signs of slug and leatherjacket damage, particularly if emergence is delayed due to cold conditions.
September 2014
Cereals
Planning for greening
New rules will take effect from 2015 onwards under the new CAP regime. Whilst May 2015 seems a long time away, decisions taken now on arable farms will form part of next year’s claim. When planning autumn drilling it is important to consider options necessary for meeting the Crop Diversification requirements and where applicable Ecological Focus Area requirements. Details of these are available on the DARD website.
Soil analysis
Following harvest is an ideal time to carry out soil testing. Use soil analysis results, in conjunction with the DARD Crop Nutrient Calculator, to correctly calculate crop requirements within nitrate and phosphate regulations. Low pH fields can be identified and rectified with applications of lime. Maintaining the correct soil pH is vital for the efficient use of fertiliser and good grain yields.
Pest and virus control
Now is a good time to place bait traps to assess slug population numbers. Bait traps consist of a tea tray sized cover laid in the field with layers mash below it. Leave traps overnight and count slug numbers the next day. Four or more slugs per trap indicates a risk and slug pellets should be applied following the metaldehyde stewardship guidelines.
Controlling virus carrying aphids is crucial to eliminate the cereal virus risk. At particular risk are crops following grass and weedy stubbles as these allow wingless aphids to move directly over the ‘green bridge’ of grass onto the young crop. Firstly destroy the ‘green bridge’ with Glyphosate two weeks before ploughing. After emergence crops are still at risk from winged migrations of aphids throughout the autumn. These migrations are monitored by the Agri-Food and Biosciences Institute and populations are posted weekly on the combinable crops section of the DARD website, along with information on virus vector control through seed dressings, aphicide spray application and slug control.
Potato Management
Late season management
Regularly inspect crops to ensure blight does not establish as crops begin to senesce. Maintain blight spray programmes until after haulm desiccation. Regular trial digs indicate when tuber size has reached your market specification, allowing the correct timing of desiccation. Allow sufficient time for full skin set before harvesting the crop into the controlled environment of a store as quickly as possible before soil conditions deteriorate and reduce crop quality.
Store hygiene
Clean stores are essential in maintaining tuber health and quality post harvest. Spores of many storage diseases lie dormant in the dust and debris in stores and in boxes and equipment. Significant reductions in infection can be achieved by thoroughly power-hosing or vacuuming stores and equipment before the new crop is harvested and between different batches of potatoes, particularly if there was any disease in the previous lot. Effectiveness can be further improved by applying an approved disinfectant after initial washing or vacuuming.
Reducing damage
Mechanical damage is largely controllable but excessive damage often leads to increased problems in store and eventual down grading of the produce. All involved in harvesting and handling should be made aware of the importance of damage and bruise prevention. Damage can occur with drops from harvesters into boxes or trailers, bruising caused by insufficient soil on the web and crushing due to oversize tractor tyres running in the drill bottom.
Early identification of damage is critical and samples of the harvested crop should be taken daily, washed and inspected for damage.
Drying and curing
Drying potatoes quickly post harvesting prevents the development of skin blemish diseases and soft rots. Drying within 48 hours using positive ventilation systems significantly reduces the development of diseases such as silver scurf. The curing period immediately following harvest is one of the most important storage phases. Wound healing occurs most rapidly at high temperatures and high humidity. Maintaining the crop at 12 to 15 centigrade and 85 per cent relative humidity for a period of about two weeks, often referred to as ‘dry curing’, allows wound healing to take place, whilst minimising the risk of disease development. Ventilating the store on dry afternoons during the curing period normally provides adequate curing conditions.
May 2014
Winter cereals
Winter barley
Most crops are now progressing well through stem extension. The majority, if not all, of the nitrogen (N) should be applied by now. Some crops, particularly six row varieties on continual arable soils, may benefit from a late top-up of 30-40 kg N per hectare at flag leaf and will also require their T2 fungicide treatment soon if this has not already been applied. Ideal timing is when the flag leaf has emerged and if possible the first few awns. However, it is more important to ensure the gap between your T1 and T2 applications is within four weeks. Where the T1 was applied early there may even be a benefit from a T3 application although this will only be the case in early drilled high yield potential crops. Fungicide choices will be similar to T1 applications and should combine a traizole and SDHI mixture, for example, Siltra, Adexar, and Bontima. See the crops page on the DARD combinable crops webpage for links to HGCA fungicide decision support charts.
Winter wheat
Ensure all wheat crops have received their T1 fungicide application by GS 32 or leaf 3 emergence and also put plans in place for a timely T2 application at flag leaf emergence. In wheats T2 application to protect the flag leaf is the most important fungicide application. As with barley while growth stages are a good guide to spray timing, it is just as important to ensure the gap between the applications is less than four weeks. Delays in application of the T2 spray can result in yield losses of 0.15t per hectare per day in high disease pressure conditions.
Triazoles, for example, Opus or Proline had previously been the standard. However, these have been boosted by the new SDHI products, Adexar, Aviator Xpro, Treoris, and Seguris which are giving much better levels of disease control, as the older straight triazoles continue to lose their activity on Septoria.
Spring cereals
The most profitable timing for nitrogen top dressing is at or before the two-three leaf stage (GS 12 to 13). Later applications than this may green the crop but add little yield.
Herbicide resistance is becoming a bigger issue so aim to apply a mixture of at least two broad-spectrum herbicides whenever most of the weeds are at the two-four leaf stages. This ensures weed competition is removed at an early stage of crop development, and may allow a reduced rate of product to be used. There are also options to apply some residual herbicides more commonly used on winter cereals to provide a different mode of action and also control annual meadow grass. These are mostly off-label approvals and some details are on the crops page on the DARD combinable crops webpage.
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, your product choice should reflect this. The products mentioned previously for winter barley are also the products to use on spring barley, albeit at a lower rate.
Leatherjackets are a risk to newly established spring barley crops with crops following grass or grassy stubbles particularly at risk. Examine ten 30 cm lengths of drill at random throughout the crop. If 10 or more leatherjackets are found from the 10 lengths of drill an insecticide treatment containing chlorpyrifos is justified. When applying chlorpyrifos it is important to minimise drift and a current industry campaign is requesting everyone to use three star low drift nozzles and 20 m buffer zones when spraying this product.
April 2014
Cereal management
Winter cereal
Crops are progressing quickly and should all have received their first nitrogen (N) applications by now. Winter barley crops and forward winter wheat crops will require their main N applications as soon as possible (growth stage 30-32) if not already applied. If sulphur has not been applied this should be applied now. Aim for 25-40 kg per hectare of SO3 as most of Northern Ireland is now classed as sulphur deficient. Where organic manures have been applied, particularly during the spring , these may have supplied some of this requirement and should be taken into account. Also apply any remaining potash requirement now as uptake of N is linked to potash availability and a shortage of potash can result in reduced N use efficiency.
Most crops were treated with autumn residual herbicides but should still be inspected for any broad-leaved weed emergence and these can be treated as soon as conditions allow. Wild oats, which are still a notifiable weed and can impact on Single Farm Payment eligibility, should also be controlled when they are actively growing. It is important to ensure as many spring germinating wild oat plants have emerged before application. However ensure herbicides are applied before the latest application timing on the relevant product labels. Also with many wild oat products there are restrictions on sequences with herbicides and growth regulators so ensure these are met to prevent crop damage.
Disease control
With crops being better tillered than last year a lot of yield potential exists but this also increases the risk of disease. Early sown crops already have high levels of disease. Most winter barley crops should have received their first T1 fungicide by now and options for this were dealt with last month and are available on the crops page on the DARD website. If a T1 fungicude has not been applied, and the crop did not receive a T0 fungicide, rates need to be kept relatively high to help control infection in the crop. The next main timing for fungicide application is the T2 which should be applied around growth stage 39. Fungicide options are similar to T1 sprays and again rates depend on disease levels at the time of spraying. For winter wheat some crops have received T0 fungicide sprays by now. Where fungicide has not been applied at T0, the T1 fungicide application will be critical to get on top of Septoria control. Apply around growth stage 32 or ideally leaf three emerging. For the T1 use robust rates of Triazole, for example, Ignite or Proline mixed with an SDHI. Links to HGCA fungicide decision support charts can be found on the crops page of the DARD website along with growth stage charts to help plan your fungicide programmes.
Spring barley
As we are now past mid March yield potential is being lost through delays with drilling. Sowing should take place as soon as a good seedbed can be created. The chosen seed rate, calculated from the thousand-grain weight, should be between 350 and 400 grains per square metre.
Monitor crops already sown for signs of slug and leatherjacket damage particularly if emergence is delayed due to cold conditions. Also make plans to treat weeds in emerging crops as soon as possible. Earlier treatment will allow a wider range of products to be used, helping manage resistant broad-leaved weeds, and also target annual meadow grass. Further details of options are available on the crops page of the DARD website.
March 2014
Winter Cereals
The cooler conditions in January and February helped hold forward crops at bay and have made spring management of these cops easier. When field conditions permit, winter crops will require their first application of nitrogen as soon as possible where this has not been applied already. Aim to apply one third of the total nitrogen (N) top dressing should be applied to winter crops during late tillering ( by mid-march for winter barley and mid/late March in winter wheat). The remainder can then be applied during early stem extension, Growth Stage (GS) 30-32, which, for winter barley, is reached in early/mid April and by winter wheat in late April/early May. For crops on continual arable rotations and where no organic manures have been applied there may be a benefit with holding 30-40kg per hectare of N until the flag leaf is emerging at Growth Stage (GS) 37. Any remaining P&K requirements should be applied now according to soil analysis. Most of Northern Ireland would now be considered as deficient in Sulphur and hence require applications of sulphur fertiliser. Risk of deficiency is highest where soils are light and rainfall is low. Winter cereals should receive 20 Kg S /ha (50 Kg SO3 /ha) in the spring before GS 32. This is most conveniently applied as ammonium sulphate which will also add nitrogen or if potash is required sulphate of potash can also be a good source.
Any remaining grass weed control should be carried out on winter cereals as soon as possible before annual meadow grass reaches tillering. Carefully check product labels for cut-off dates and growth stages.
Disease Control
Some disease is already active in earlier sown crops of winter barley and these crops may benefit from a T 0 application of fungicide to prevent too much pressure on the main T1 spray. Products such as cyprodinil (Kayak) will provide good protectant activity. Lush winter barley crops will require a robust T 1 spray in late March or Early April at growth stage 30-31 to control Rhyncosporium and mildew. Rates will need to be kept high particularly if a T 0 has not been applied. Use a strong triazole such as prothioconazole (Proline) which could be mixed with chlorothalonil (Bravo) or on higher yield potential crops an SDHI fungicide (Imtrex or Vertisan). Co formulations are also available (Siltra,Adexar Bontima).
For winter wheat crops the main spray is a well timed T1 at growth stage 31-32 which will generally be mid to late April. This should be based on a robust rate of triazole (Proline or Ignite) combined with an SDHI or mixtures as above. Again in lush crops a T 0 application of a protectant such as chlorothalonil (Bravo) may help take the pressure of the T1 spray. If yellow rust is considered a threat then addition of a triazole with good rust activity could help at this stage also. Links to HGCA fungicide decision support charts can be found on the crops page of the DARD internet site along with growth stage charts to help plan your programmes.
Drilling Spring Barley
Sowing should take place as soon as a good seedbed can be created. The chosen seed rate, calculated from the thousand-grain weight, should lie between 350 and 400 grains per square metre. The lower rate should suffice for March-sown barley drilled into a good seedbed, however in poorer conditions, or if sowing later, the higher rate is preferable. Monitor spring sown crops for signs of slug and leatherjacket damage particularly if emergence is delayed due to cold conditions.
January 2014
Cereals
Winter cereals
Following a good autumn most winter cereal crops are well established with the exception of late drilled wheat crops after potatoes and forage maize, some of which have only just emerged. Any residual weed control applications should be made as soon as possible aiming to target annual meadow grass before it reaches tillering. Check product labels carefully for latest application timings as some autumn products have a 31 December cut-off date.
Plant counts are generally good in late drilled crops and some early nitrogen (30-40 kg per hectare) in late February or early March will help these crops tiller to achieve full yield potential. For better established crops tiller number counts should be made in mid to late February to help plan nitrogen timing. Where tiller counts are close to 1100 per square metre for winter barley and 900 per square metre for winter wheat, then apply one third of the total nitrogen top dressing during late tillering (late February/early March in winter barley, mid/late March in winter wheat). For thicker crops, with tiller counts above these levels, reduce and delay early nitrogen applications to prevent excessive tillering which can leave crops more prone to lodging. Apply any remaining crop phosphorus and potassium requirements during February and March.
Spring cereals
Now is the time to carry out soil analysis on any land intended for spring cereals. The recommended list of cereal varieties for Northern Ireland has just been released by AFBI and will be available at the Arable Conference on the 21 January and on the AFBI website. Order seed early to ensure the best varieties can be grown and have the seed on farm to allow early drilling where possible. Local research has shown that yield potential is lost when spring barley drilling is delayed beyond mid-March. One month’s delay can lead to a 2 tonne per hectare yield reduction.
CAP reform
Early indications are that CAP reform could pose some implications which will require careful planning by cereal and potato growers. While all details are not yet fully clarified there will be an opportunity to update yourself on the current position at the CAFRE,UAS, UFU Arable Conference on 21January at Greenmount Campus, Antrim. To register phone 028 9442 6772.
September 2013
Soil analysis
Following harvest is an ideal time to carry out soil analysis. Use the soil analysis results together with the Crop Nutrient Recommendation Calculator on the DARD website (www.dardni.gov.uk) to correctly calculate crop requirements within the Nitrates and Phosphates regulations. In addition, fields with a low pH can be identified and rectified with applications of lime. This input is often overlooked, but having the correct lime status is vital to ensure efficient use of fertiliser and good grain yields.
Controlling viruses
Crops following grass, or weedy stubbles, are particularly at risk from wingless aphids moving directly over this ‘green bridge’ of grass onto the young crop. To prevent this destroy the ‘green bridge’ by using glyphosate two weeks before ploughing. All crops however are still at risk from winged migrations of aphids throughout the autumn. These migrations are monitored by AFBI and results are posted on the crop monitor section of the DARD website. When numbers are high, an aphicide approved for BYDV vector control should be applied at emergence. Another option is to plant seed treated with an aphicide, such as Deter, which will give systemic control for most of the season.
Slug monitoring
Slug damage was a big problem in autumn cereals last year. Now is a good time to place bait traps to assess population numbers. Bait traps should consist of a tea tray sized sheet of plastic laid in the field with layers mash below it. Leave these overnight and count the number of slugs present the next day. A catch of four or more slugs per trap indicates a risk. Apply slug pellets following the metaldehyde stewardship guidelines, details of which are available on the combinable crops section of the DARD website.
Early autumn drilling
Last season caused problems for establishment of winter crops particularly later in the season. Some of these problems can be avoided by sowing earlier, before the end of September, where possible. To avoid problems with lodging it is critical that seed rates are reduced in earlier sown crops by around 20 per cent in winter barley crops and up to 40-50 per cent in winter wheat.
May 2013
A very cold March followed by cool early April weather has meant that winter cereals are less developed than normal. One benefit is that the cold conditions have also slowed development of foliar disease on winter cereals. Main nitrogen top dressings and any remaining phosphate, potash and sulphur applications should however be applied to most winter crops by now so that, as conditions warm up, there will be nutrients in the ground to meet the rapid growth phase through to ear emergence. Spring barley crops have been drilled later this year and the cold soils have resulted in slower than expected emergence which will impact on yield potential.
Winter cereals
Winter barley
Some crops will still need to receive their first T1 fungicide application. Do this as soon as possible to prevent disease becoming established on the plants. Spray winter barley with a robust rate of fungicide. Siltra, Adexar and Bontima are the current standards. For thinner crops with lower yield potential triazole strobilurin mixtures, such as, Fandango will provide a cost effective result. Target the T2 fungicide application for winter barley at early awn emergence (GS 49). However, monitor crops carefully as the presence of active rhynchosporium lesions may require an earlier timing and also monitor the period between fungicide applications and try to keep it between three to four weeks to avoid gaps in protection.
Winter wheat
Ensure all wheat crops have received their T1 fungicide application by GS 32. A triazole (for example, Opus or Proline) had previously been the standard. However, these have been boosted by the new SDHI products, Adexar, Aviator Xpro and Seguris which are giving much better levels of disease control, as the older straight triazoles continue to lose their activity on Septoria.
Spring cereals
The most profitable timing for nitrogen top dressing is at, or before, the two to three leaf stage (GS 12 to 13). Later applications than this may green the crop but add little yield. Avoid excessive applications of nitrogen, and keep on the right side of the law, by fully taking into account any organic manure applications or nitrogen contribution from previous cropping.
Aim to apply a mixture of at least two broad-spectrum herbicides whenever most of the weeds are at the two to four leaf stages. This will ensure that weed competition is removed at an early stage of crop development, and may allow a reduced rate of product to be used. It is also good practice to prevent the establishment of disease at this stage by tank-mixing a fungicide with your herbicide. As rhynchosporium is the most damaging disease in our current spring barley varieties, your product choice should reflect this. The products mentioned previously for winter barley are also the products to use on spring barley, albeit, at a lower rate.
Leatherjackets are a risk to newly established spring barley crops.
Crops following grass or grassy stubbles are particularly at risk. Examine ten 30 cm lengths of drill at random throughout the crop. If ten or more leatherjackets are found from the ten lengths of drill, an insecticide treatment containing chlorpyrifos is justified.
Further detailed information on fungicide choice for cereals can be obtained on the HGCA web site
April 2013
Winter cereals
Early sown crops have managed to come through the winter with little damage, apart from low lying areas in fields where saturated soil has thinned plant numbers. Recently, however, winter barley and wheat have shown signs of yellowing. This is the plant’s way of telling us they need their first top dressing of nitrogen fertiliser to kick-start growth if this has not already been applied. Later sown crops have struggled during the cold winter and will require nitrogen to encourage tillering as soon as possible. Early applications of a chlormequat or trinexapac-ethyl based product, for example, Moddus can also help maintain tiller numbers but conditions need to be suitable.
Growth stage (GS) 31 (first node detectable) is the best time to apply the main nitrogen top dressing to winter cereals and some winter barley crops have already reached this important growth stage. All cereals, especially those on light, sandy or free-draining soils, will be at risk from sulphur deficiency so they should receive 15 to 35KG sulphur per hectare in spring. This can be done most conveniently by applying a sulphur containing nitrogen fertiliser.
Weed control
Given the wet autumn and winter few fields have received a residual autumn herbicide. As most of these products are designed to be applied to small, emerging weeds, a spring application may not be effective and switching to a herbicide designed for use on spring cereals may be the way to go.
Lodging control
The key growth regulator timing to reduce lodging in winter crops is early stem extension (GS30 to 31). A chlormequat or trinexapac-ethyl based product, for example, Moddus is most effective, when applied at this time, to all but the thinnest crops as a precaution against lodging.
Controlling disease
Rhynchosporium in barley and Septoria tritici in wheat are the two main disease threats. Spray winter barley at GS31 (first node detectable) with a robust rate of fungicide. Siltra, Adexar and Bontima are the current standards and they promise cleaner crops and more profit for the grower. These come from different chemical families than those that we have been used to and are novel in their mode of action.
Winter wheat should also receive its first fungicide spray as soon as leaf three has emerged. This normally coincides with GS32 (second node detectable). A triazole (for example, Opus or Proline) had previously been the standard. However, these have been aided by the new products, Adexar, Aviator Xpro and Seguris which are maintaining levels of disease control, as the older triazoles continue to lose their activity on Septoria. Triazole mixture products (for example, Brutus, Prosaro or Kestrel) are also proving beneficial in high risk situations. You are strongly advised to use an anti resistance strategy in your fungicide programmes and inclusion of chlorothalonil (for example, Bravo) in the mixture will help protect the new chemistry.
Spring barley
Benchmarking results show the most profitable spring barley growers drill their crop as early as soil conditions allow. Complete spring barley sowing as soon as possible using seed rates between 160KG per hectare (10.2 stone per acre) and 180KG per hectare (11 stone per acre) depending on thousand grain weight of the sample. As crops begin to emerge look out for signs of leatherjacket damage, especially in crops following grass or grassy stubbles. If a problem is identified, treat the crop with chlorpyrifos, for example, Dursban.
March 2013
Winter cereal nitrogen application
Following a cold and wet autumn and winter many crops are thin and patchy. Early decisions will have to be made regarding the fate of these crops.
For winter wheat plant populations as low as 30 plants per square metre can still provide an economic return especially when the cost of redrilling with a spring cereal is taken into account. For these thin crops early applications of nitrogen (N) will help encourage tillering, and if not already done, apply 30-40 KG per hectare as soon as possible. For better established crops one third of the total N top dressing should be applied to winter cereals during late tillering (late February/early March in winter barley, mid/late March in winter wheat). The remainder can then be applied during early stem extension, Growth Stage (GS) 30-32, which, for winter barley, is reached in early/mid April and by winter wheat in late April/early May. For crops on continual cropping rotations, and where no organic manures have been applied, there may be a benefit withholding 30-40 KG per hectare of N until the flag leaf is emerging at GS 37.
The need for sulphur
Since 1985 atmospheric deposition of sulphur (S) has fallen by more than 25 percent in Northern Ireland. Risk of deficiency is highest where soils are light and rainfall is low. Winter cereals should receive 20 KG S per hectare (50 KG SO3 per hectare) in the spring before GS 32. This is most conveniently applied as ammonium sulphate which will also add nitrogen.
Disease control
As growth has been slow this winter disease build up will be less of an issue, but crops will still require preventative treatments, as once established most foliar diseases of cereals are difficult to eradicate. Mildew and Rhynchosporium are the diseases most likely to be present in winter barley during March. Only where these diseases are at a high level and are actively invading the new growth would a fungicide be economically justified before GS 30-31 (T1 timing). If disease levels require early spraying T0, use a reduced rate of an appropriate fungicide and follow up with a full rate spray at T1.
Drilling spring barley
With the reduced plantings of winter cereals last autumn the spring barley area will be increased this year and benchmarking shows maximising yield is key to the profitability of cereal enterprises. The key determinant of spring barley yield is sowing date. One month’s delay in sowing often leads to a yield reduction of around 2 tonne per hectare.
Sowing should take place as soon as a good seedbed can be created. The chosen seed rate, calculated from the thousand-grain weight, should lie between 350 and 400 grains per square metre. The lower rate should suffice for March sown barley drilled into a good seedbed, however, in poorer conditions, or if sowing later, the higher rate is preferable. Slugs have been a particular issue in establishing winter cereals and you should monitor spring sown crops for signs of slug and leatherjacket damage particularly if emergence is delayed due to cold conditions.