Winter crop technical update

Author: George Blackburn 


As we move into the second half of February and look towards the beginning of March, our attention must first focus on the winter crops in the ground from autumn 2021. Key management decisions regarding fertiliser and growth regulation in the early stages of spring can have a major bearing on a crops final yield potential especially winter barley.

There is a slight increase in the overall acreage of winter cereals as sowing conditions were good in the early part of autumn 2021, with many growers opting to drill a little earlier to get crops established. The sense of optimism amongst growers following last year’s exceptional harvest was a welcome boost to the sector and as a result, growers were eager to get crops planted. The earlier drilled crops have better establishment without question and did receive an autumn aphicide. Those that took the gamble of sowing earlier into better conditions seem to have been rewarded so far but time will tell on this. The winter has been a lot milder than normal so many early drilled crops are quite advanced in terms of growth stages. Growth regulation and delaying applications of fertiliser on these earlier crops will be wise this spring. The huge increase in fertiliser prices has tempered some of last year’s optimism, however, grain prices look very strong for the coming harvest and many growers have availed of attractive forward prices. When planning fertiliser strategies for the coming season regardless of price, the focus must be on growing a crop to its full potential. This has always proven to be the most profitable strategy. Soil sampling and correct liming are key steps required to produce optimum yielding crops for the coming season.


Winter Barley

Winter barley crops have established well, with good plant count levels. Most were sown in ideal sowing conditions and have come through a very dry winter. Some of the crops are a little bit forward, with some live disease in them and will require robust growth regulation programmes. Any crops that have not received any Phosphorus (P) and Potassium (K) will need an application before the end of February as soon as conditions allow. Crops that received no autumn P and K will start to show up deficiencies especially for P when temperatures pick up and growth kicks in.
Check your soil samples and tailor NPK compounds accordingly. As a rule of thumb, winter barley crops need 30-35 units of P and 100 units of K. This will vary slightly between 2 row and 6 row varieties, with slightly higher potash requirements for the 6 rows. Aim to have 75% of Nitrogen (N) out on winter barley by March 20th. Disease levels are generally low, growth regulation and tillering will be the main focus of early chemical applications. Do not be tempted to drop back on P and K applications too much as we must remember that offtakes from fields were very high last harvest.


Winter Wheat

Winter wheat crops are generally good but there is some variation out in the fields. Crops sowed earlier that are well established are in good heart, with excellent plant stands. Crops sown later in difficult seedbeds, especially potatoes and fodder beet have suffered a bit with crow and slug damage. Chopped bean straw has also proven to be a suitable host for slugs and a few winter wheat crops after beans have needed to be treated with slug pellets. It is becoming increasingly more important to run a shallow disc over chopped bean or rape straw and is an important part of the Straw Incorporation Measure for slug control. Our methods of chemical control are no longer as potent as they used to be. Many crops after beans have a lot of volunteers coming through but these will be easily dealt with in the spring and are actually serving a useful drainage purpose at the moment by soaking up moisture from the soil.

While crops are generally good and winter wheat has an amazing ability to compensate for sub-optimal plant stands at harvest, I would be reluctant to tear up any crops bar they are very poor. Aim to have a balance of P and K out on wheat by mid-March. Apply according to soil sample requirements. Aim to have the first main split of nitrogen on by the first week of April and final split on the first week of May. It is important to remember that wheat should not have too big a canopy too early in the crop, as this presents problems for growth regulation and disease control, especially Septoria Tritici.


Winter wheat field

Winter Oats

Winter oat crops have established well in general and there is a nice amount of winter oats in the ground. The two varieties sown are Isabel and Husky, both spring varieties sowed in the autumn. Most crops are in good condition but some in the more coastal and milder areas are a touch forward. These crops will need careful attention in terms of growth regulation and rust control especially in south Wexford and other coastal areas. Crops will need to get their NPK requirements by the middle of March with a blend such as 10-5-25 plus S for winter oats at a rate of 4 bags/acre.


Winter oat field


Winter Oilseed Rape

The acreage of oilseed rape (OSR) has seen a drastic increase this year, owing to record prices available for the crop. Crops are in excellent condition and are more forward than ever after the mild winter. The Green Area Index (GAI) of each crop is worth measuring this year and there are a few useful apps available to measure this. Some crops have up to 3.5 GAI readings and are exceptionally forward. The key message for these crops would be to delay N applications for as long as possible and also to reduce overall N applied. Most crops are in the range of 2-2.5 GAI which is excellent coming out of the winter and there is an opportunity to reduce N applications by 50-60 units on these crops.

Pigeon damage doesn’t seem to be much of an issue at all this year. All crops received some P at planting and this has made a big difference to rooting and overall establishment. All crops have been treated with a fungicide for light leaf spot in the autumn and with Kerb (propyzamide) for grass weed control. Most crops received an autumn growth regulator which seems to have worked very well to even out crops for nice canopy management in the spring. As a result, crops have nice clean canopies for the onset of spring. Aim to get potash out on OSR by mid-March, 100-110 units is sufficient. Rape has a high requirement for Sulphur (S) so the first main split of N should include ASN (26% N + 14% S), with further applications of Sulcan. Aim to apply the last 40-50 units of N on rape at the latest possible time that the fertiliser spreader can physically travel through the crop.

Winter oilseed rape


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Herbicide resistance in tillage farming

Author: Jimmy Staples


Over the last decade, it has become increasingly difficult to manage some of the pests that we were previously able to control comfortably with plant protection products.

This can be attributed to:

  • The loss of key active ingredients due to de-registration
  • A lack of new active ingredients coming onto the market
  • The development of resistance to the current active ingredients on the market


Loss of active ingredients

The loss of active ingredients is a worrying trend and according to the DAFM website, there were 17 active ingredients whose registration was revoked between December 31st 2018 and August 23rd 2020. The last date for use of many of these active ingredients has now passed with the loss of chlorothalonil (Bravo) and the neonicotinoid family of insecticides creating big challenges.


Resistance in the tillage field

This loss of key active ingredients is compounded further by the development of herbicide resistance. BYDV control can be challenging due to pyrethroid resistance within some species of aphids. Diseases like Septoria are constantly putting available chemistry to the test and resistance to herbicides is becoming increasingly common throughout the country.

We have both broad-leaved and grass weed resistance confirmed here in Ireland and it is suggested that this is under-reported. Here in Wexford, I have come across resistant populations of chickweed, corn marigold and wild oats and I am currently awaiting results from Teagasc in relation to populations of blackgrass and Italian ryegrass which may also be resistant.


Reported weed resistance to one or more herbicide - table


Cultural control: Integrated Pest Management 

The Enable Conservation Project has confirmed herbicide resistance in Italian ryegrass, blackgrass and wild oats. Blackgrass and Italian ryegrass populations have been found to be resistant to ALS herbicides (Alister Flex, Pacifica Plus, Broadway Star, Monolith), ACCase herbicides (Axial Pro, Falcon, Stratos Ultra) and in some instances, a combination of both. Where both ALS and ACCase resistance are present, it severely limits your crop herbicide options.

In these cases, Integrated Pest Management (IPM) strategies need to be to the fore and there are many options available. These include but are not limited to:


  • Use of rotations
  • Cover crops
  • Companion cropping
  • Arable grass margins
  • Using competitive cultivars
  • Pushing back sowing dates
  • Increasing seeding rates
  • Stale seedbeds
  • Cultivation type and depth
  • Establishment system
  • Rogueing
  • Crop destruction
  • Remote sensing
  • Monitoring and evaluation

A successful IPM strategy will consist of a number of these measures chosen specifically to meet the challenges of an individual’s farm and should be used along with the targeted application of herbicides. These should be implemented in a structured fashion over the course of the whole rotation. Achieving effective control of many of these weeds will not be possible in one, two or even three years.


Herbicide resistance management strategy 

Prevention of course is better than a cure and there is simple, yet effective measures that we can take to try and ensure that herbicide resistance does not evolve on farm. Most of these measures will revolve around the use of and application of herbicides.

When spraying, consider the following as part of a herbicide resistance management strategy:

  1. Has the target weed(s) been identified correctly?
  2. What is the target growth stage and when is the weed going to be at this stage?
  3. What volume of water do I need to use to ensure sufficient coverage?
  4. Do I have issues with the pH in the water I am using?
  5. What rate of herbicide do I need to achieve control of the weed(s) at the target growth stage?
  6. Try to keep tank mixes as simple as possible, so as not to stress the crop and ensure that all components of the mix work effectively. 


Some things are outside of our control. The last two springs have been incredibly challenging with weather conditions either too wet or too cold and the variations in day and night-time temperatures meant spraying days were very limited. I came across a number of cases of wild oats and sterile brome which were not controlled by herbicides in both 2020 and 2021. Samples were sent for resistance testing and results have shown that they were not resistant to the products used. A number of factors contributed to the lack of control, namely, big variations in day and night-time temperatures, shading from the crop and the use of lower rates of herbicide than was required.

It is important to understand the weeds on your farm as this will help you to decide on management strategies. For instance, it can take from five to ten years for resistance to develop in a population of wild oats as opposed to a population of blackgrass where resistance can develop in just three generations.

If you do suspect herbicide resistance on your farm, please get in contact with your advisor as the earlier the problem is diagnosed and action is taken, the greater the chance of a positive outcome.


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Promoting early calf husbandry

Author: John Bass 


Calf husbandry and nutrition are very topical at this time of year with many dairy and beef farmers rearing calves by hand on whole milk or milk replacer. Getting calves off to a good start is critical for their development, their feed conversion efficiency and also their subsequent production. Getting dairy heifer calves off to the correct start in life will not only maximise output but will also increase their longevity within the herd.



It is important to follow these simple steps as soon as a calf is born to ensure calf health and thrive:

  • It is important to give a newborn calf 3 litres of colostrum within the first 2 hours of life.
  • Ensure the first feed is the first milk from the cow after calving.
  • Check colostrum quality using a refractometer as quality varies from cow to cow.
  • Ensure a calf receives an adequate quantity of quality colostrum as it will provide the required antibodies and immunoglobulins to help boost the calf immune system.
  • Bottle feeding is often the best way of ensuring the calf has received an adequate volume.
  • If you are storing colostrum in the fridge, ensure a temperature of 4°C. Store it for no longer than 2 days as the level of antibodies declines rapidly thereafter.
  • When freezing colostrum, do so in small packs for ease of defrosting. Defrost slowly on a low heat below 50°C so you don’t reduce the number of antibodies.


Newborn calves drinking milk replacer from milk bar


Milk Replacer Vs Whole Milk 

It is advantageous to feed milk replacer after day 2 or 3 as it minimises disease spread when compared to whole milk. Calves require approximately 13% of their bodyweight in feed intake in the first week of life, which should be split between 2-4 feeds per day. In week two, this requirement increases to 15% of their bodyweight equating to about 6 litres per day for a 40 kg calf. Calves at 2-3 weeks of age have the potential to achieve 750-950 grams of live-weight gain per day, with a minimum target of 500 grams. Feed conversion efficiency is almost at 1:1 so the quality of milk fed must be high enough to ensure the daily intake is providing enough energy to meet demand.

Milk powders can vary in quality; skim or whey are more favourable than those based on vegetable proteins as they are more easily digested by calves. Like with whole milk, milk replacers need to be mixed and fed at the correct temperatures (37-39°C) and the correct concentration to ensure adequate nutrient intake. Aim for powders with a minimum of 23% protein and 17% fat and below 0.1% fibre. Mix 125 grams powder with 850mls of water which provides 1 litre of milk replacer. Feed 6 litres of milk per calf per day, this volume can be increased to meet demand if necessary.



It is important to introduce a high-quality ration or nut from day 2-3. Ensure it has a high cereal grain content and is highly palatable with no dust. Initial intakes will be small so keep quantities low and fresh. Early intake of cereal-based feed will rapidly increase the rumen development of the calf and the growth of papillae on the rumen wall, which will increase nutrient uptake capacity of the calf throughout its life. Failing to feed concentrates at an early stage will have drawbacks later in life. Aim to have calves consuming 1kg of concentrates at weaning.

Keep feed fresh and easily accessible in order to increase intakes from an early age. A high-grade nut can be advantageous as it is cleaner with less dust than a coarse ration and less attractive to birds which can bring harmful bacteria and diseases into sheds.

Claves at the feed barrier with concentrates



A fresh straw bed is important for calf comfort and health and it will also encourage fibre intake which will aid rumen development. Ensure calves have adequate feeding and resting space and that pens are well drained and ventilated. Regular cleaning and liming is a must to reduce the risk of any scours or other illnesses. Ensure there is a constant supply of fresh clean drinking water and that feeders and drinkers are at an accessible height for calves also.

A bright well-ventilated shed with no draughts at calf level is essential to avoid calves getting cold. Good ventilation will also ensure enough airflow above calf level to minimise respiratory problems and keep the air fresh.

Calves housed indoors


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NEW – Terra Range brochure available to download

Target Fertilisers are committed to the future of agriculture in Ireland through fertiliser and sustainable fertiliser usage. They are constantly looking at methods of maximising production through environmentally friendly and efficient uses of fertiliser. As a result, they have joined forces with Brandon Biosciences to develop a new range of sustainable fertiliser products, the Terra Range.

To learn more about the new Terra Range and how it can benefit your farm, download the new brochure here:


Terra Range brochure

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SlurryBugs®: Treating slurry more important than ever

Author: Philip Kennedy


In recent years, farmers are becoming increasingly aware of the benefits of treating slurry, however many have yet to make it a part of their nutrient management tool.

There are many slurry treatments on the market, however in this article, we will look at SlurryBugs® ; what it is, how does it work and what are the benefits of using it on farm?


What is SlurryBugs®?

SlurryBugs® is a bacterial slurry additive which breaks down the solid content producing a more homogenous and nutrient rich fertiliser.

It contains soil originating bacteria, enzymes and micro-nutrients which enhance the retention of nutrients within stored farm slurry. This can lead to significant savings on chemical fertilisers and enhance soil quality as well as reducing ammonia odour and losses.


How do SlurryBugs® work?

Slurrybug product packaging

  1. The bacteria retain nitrogen by capturing the ammonia within the urine. The nitrogen is fixed into a slow-release form of organic nitrogen which is readily available for plant uptake.
  2. The enzymes actively degrade the undigested fibre within the effluent which improves the consistency and reduces odour.
  3. The micro-nutrients provide a vital food source for the bacteria allowing more nutrients to be retained by the bacteria in an organic form.


CF - SlurryBugs Stats

Analytical results of SlurryBugs® part 2


What are the results?

A demonstration of the flow of organisms, nutrients and chemicals known as the BioCircle

  • Reduces odour

Most slurry odours are caused by ammonia being released into the atmosphere. When SlurryBugs® are used in conjunction with LESS (Low Emission Slurry Spreading) slurry application methods, there is almost no odour released from the slurry spread on the land. This is a result of fewer gases building up as the bugs increase nutrient retention.

  • Reduces fibrous crust

SlurryBugs® will reduce crust formation on top of the slurry, leaving it consistent. This will reduce agitation times and lead to less blockages, especially when spreading with LESS equipment.

  • Minimises need for stirring

After a few years of use, the bugs will build up in the tank and the need to agitate will reduce and slurry will stay homogenous for longer. This will mean a fuel saving up to 25%.

The continued use of the product will improve microbial activity in the slurry and the soil. The slurry pH will be raised to allow soil bugs to work at optimal. Microbial activity is greatly reduced in acidic untreated slurry.

  • Improves fertiliser value

Nitrogen availability and retention can increase up to 50% in treated slurry. This combined with LESS application methods can greatly decrease ammonia losses and therefore increase the amount of nitrogen used from slurry application. With all the above combined a typical 2,500 gals per acre application rate of slurry in spring should give you 25 to 33 units per acre of nitrogen. The nitrogen in this example is worth approximately €35 per acre.



How to apply SlurryBugs®?

  • Each 1 kg pot treats 100,000 gallons (450,000ltrs).
  • The product should be applied when slurry levels are low in tanks and at least 4-6 weeks before spreading to allow the bugs to work and multiply.
  • The slurry bugs can be mixed in a bucket of lukewarm water and then poured into lagoons, channels or directly into the tank.


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Dairy cows grazing grass

Dosing Advice: Combating Lungworm In Your Herd

Author: James O’Neill 


Lungworm infections in your herd can cause a severe and often fatal disease that is commonly called hoose. A lungworm infestation is caused by exposure of grazing animals to lungworm larvae on a pasture. The lifecycle of the lungworm is about four weeks long i.e., from the ingestion of larvae to the excretion of infective larvae by the affected animal. In the worst case, within four weeks of ingesting lungworm larvae, the cow or calf can be shedding millions of fresh larvae onto the pasture via their faeces and is most commonly seen from August to October.

Lungworm: Spotting The Early Signs

Early signs to look out for include coughing, initially after exercise and then at rest, with an increased respiratory rate. Left untreated, cattle will often lose weight, with noticeable deterioration taking place in their body condition. Dairy cattle may also experience a sudden and dramatic drop in milk yield.

Rain can disperse larvae in contaminated faeces, while warm, moist conditions keep infective larvae alive and encourage fungal growth. Larvae often make use of the fungal spore, Pilobolus (found on cattle dung), to disperse themselves on a pasture. Generally, conditions that favour the growth of pasture also favour the development of the infective larval stage L3, which is why outbreaks peak in late summer and early autumn. A dry season followed by a damp one has always encouraged outbreaks as this creates a natural immunity gap.


Treat infected cattle as early as possible because there may be varying degrees of infection in any one group. Levamisole (Levafas Dimond) and white drenches (Tramazole) will take out what parasites are there on the day of treatment and have no residual effect. Macrocyclic Lactones such as Ivermectin (Acomec Pour-On, Ivomec injection and Eprizero Pour-On) will give longer protection (28-120 days is typical). The product used will have a bearing on subsequent grazing management post-treatment. Calves that were heavily infected need to be closely observed for 1-2 days post-treatment.


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Mineral supplementation

Mineral Supplementation Guide

Author: John Bass 


The time of year has come once again to start planning for the coming winter, and with that, decisions need to be made on winter diets and mineral supplementation. The best way to start is by undertaking a nutrient and mineral analysis on silage in order to make a plan on what supplementation is needed to balance the feed value and also any mineral shortfalls. Results of silage analysis so far this season have indicated that quality is mixed, with a lot of June cut silage lacking in dry matter digestibility (DMD) as well as protein and energy. This is a result of large crops of grass being cut at a later growth stage due to unfavourable weather conditions.

Mineral Supplementation 

After balancing the protein and energy requirements to meet the animal’s needs i.e., milking cows or dry stock, it is vital that we look at the mineral requirements of each animal to get the correct level of macro and micronutrients. The intensity of livestock farming has increased a lot in recent years especially in the dairy herd. This has led to a lot of silage being cut off out-farms, often too far to draw dung and slurry, meaning land is becoming depleted of key nutrients and minerals. The result is silage that is very low in minerals.


mineral supplementation


There are many ways to feed mineral supplements, however unfortunately, the most convenient methods for the farmer aren’t always the most beneficial to the animal. For example, dusting on top of the feed is simple, however lack of adequate feed space and dominance within the herd can mean that some animals will take in a lot more than others. Therefore, it is important to mix powder minerals through the feed to ensure a constant and regulated intake by each animal. This also goes for block-based molasses or salt licks as intakes will vary depending on the product and the availability to the animal, leading to an over or undersupply to certain animals, which can negatively impact on health and vigour.

The most reliable way to feed minerals is to mix through concentrated feeds. This is especially the case with macronutrients, while topping up micronutrients using boluses or doses ensures each animal is receiving the recommended supply. It is also important to feed the right levels of certain minerals at certain times especially with calving cows. E.g. Supply high magnesium (Mg) pre-calving and high calcium (Ca) post-calving to help avoid milk fever.


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winter feeding

Winter Feeding 2021

Author: Jack Scallan  


Early silage analysis results indicate that silage is not of the usual high quality this year. This is not surprising as grass growth and quality were poor during the spring and summer periods. Poor growth rates, low protein levels and variable energy levels in grass lead to very low milk urea levels throughout the summer. The low protein in the grass caused many cows to fall short of their peak milk production. The growth rates, protein, and energy levels in grass recovered in the autumn but grass dry matter (DM) dropped which created issues with intakes and clean out of paddocks.

Silage Analysis Results 

The preliminary silage results are showing that the dry matter is high (25 to 30%), while protein and energy are low. The digestibility (DMD) is ranging from about 65 to 70%. As a result of the low nutrient value in combination with the high DM, some animals may not get their full nutrient requirement from silage alone. Therefore, it will be necessary to give these animals some supplementation over the winter period.

Concentrate Feeding 

The level of supplementation or meal feeding will initially depend on the silage analysis but also on the stock type, body condition score (BCS), target weights, and in the case of beef stock, daily live-weight gain (DLWG) and finishing weight.

Youngstock and weanlings should receive between 1 and 2 kg of a 16% concentrate, either nuts or coarse ration that has a UFL of at least 0.95 and contain good quality ingredients, such as barley, soya bean meal, beet pulp or maize meal. Particular attention should be given to replacement heifers this year as they need to achieve a target weight of 340 to 360kg at first service, while first-time calvers should be at 540 to 560kg at calving. Bodyweight at first calving depends on breed, age, etc., and should be approximately 90% of the cow’s mature weight.

Cows usually wouldn’t need any supplementation in the dry period where silage quality is average to good. This year, meal feeding may be required. This will be dependent on silage analysis and BCS. BCS should be 3.0 at drying off and 3.25 at calving. So far this year, cows have held their condition well and it should be maintained through the dry period. If supplementation is required, then up to 2.5kg/head/day should be adequate. Ideal supplementation options are a good pre-calver concentrate or a combination of straights such as barley, oats, maize meal or soya bean meal.


Cows eating silage


Particular attention should be given to first lactation cows as they can lose condition rapidly and find it difficult to build it back up. Housing them separately from the main herd is desirable, as they can be fed extra concentrate without excessive bullying from older cows.

Forward store cattle and finishing cattle will need a very high-energy diet to reach their target weights. A concentrate with 0.98 UFL or 0.97 UFV and a crude protein of 13 to 15%, should be adequate to achieve these targets with this year’s silage.

In all cases, a good source of fresh clean water must be available to counteract the high DM in the silage. If you have any queries regarding silage and its quality or if you wish to get your silage analysed, please contact your Cooney Furlong Representative or your local branch. 


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Achieving Effective Grass Weed Control

Author: Jimmy Staples 


Harvest 2021 will be remembered for several reasons; good weather, excellent yields and high prices. With sowing of autumn crops almost wrapped up, farmers would be forgiven for forgetting about the difficulties that they faced in the spring of this year.

Weed control was particularly challenging last season as a poor back end and a cold, wet spring left very few opportunities to spray when conditions were right. Indeed, I don’t think I spoke with a farmer this year who didn’t have at least one field where herbicide efficacy was either severely reduced or there was no control achieved.

If last spring thought us anything it is that relying solely on a spring herbicide application to control weeds is a gamble. This is further compounded by the increasing number of reports of herbicide resistance in both broad-leaved and grass weeds across the country. Worryingly, most of these weeds are being reported as having some or full resistance to the ALS family of herbicides. Examples of these are Pacifica Plus, Broadway Star, Ally, Cameo and Harmony type products which are widely used here in spring.

Autumn germinating grass weeds like blackgrass, sterile brome and Italian ryegrass can produce anywhere from 1,000 to 5,000 seeds per plant. The poor control achieved in many crops last season resulted in an increased level of seed return compared to previous years and could well make weed control for the coming year challenging.


Integrated Pest Management:

Every farm should have an Integrated Pest Management (IPM) strategy developed for their farm. This will be different for every farm as each one has its own unique circumstances and challenges. However, the fundamentals don’t change; in order to develop an IPM strategy you need to know what weeds are present on the farm and you also need to understand their biology. For instance, when do they germinate, flower and set seed?

An IPM strategy should be based around the use of cultural control options with a targeted herbicide strategy employed to achieve the highest levels of control possible. Depending on the target weed, there are a range of cultural control options available. Below are examples of these options available for autumn germinating grass weeds:

  • Rotational ploughing
  • Stale seedbeds
  • Delayed sowing
  • Spring cropping
  • Use of break crops
  • Increasing seeding rates
  • Use of competitive cultivars
  • Preventing seed return
    • Rogueing
    • Whole cropping
    • Crop destruction
  • Machine hygiene

The trick is to use as many of these options as is practically possible to both reduce the number of viable seeds in the seedbank, and more importantly, to prevent seed return. The likes of blackgrass and sterile brome seeds are short-lived in the soil and a seed decline of 70-80% per year is normal. This is especially important where resistant populations are present. Unfortunately, these challenges will not be overcome in one or even two seasons. In order to prevent populations of these grass weeds from increasing, a minimum of 95% control is needed year in year out.


Herbicide Strategy:

When considering what herbicides to use as part of your IPM strategy, there is only one place to start and that is with a pre-emergence herbicide. Pre-emergence herbicides tick many boxes.

  • They have improved efficacy as you are controlling weeds when they are very small.
  • Weather conditions around sowing time are generally quite favourable for spraying. You have longer days and soils are more trafficable compared to late October and into November.
  • Pre-emergence herbicides are an important part of your resistant management strategy as you are varying the chemistry and controlling weeds when they are at their most vulnerable.

Weed screen trials conducted last year by Teagasc in Oak Park found that the best weed control was achieved where pre-emergence herbicides were used in the program. Where autumn germinating grass weeds are a concern, using flufenacet based products (Firebird, Firebird Met, Naceto, Reliance etc.) will give you the best control. As with all plant protection products, ensure you are using the right rate for the target weed.

The use of a pre-emergence herbicide is particularly important in winter barley situations as you have no spring herbicide options available for controlling these weeds. Where you have winter wheat, using a pre-emergence product will take the pressure off the spring herbicide. Weeds that emerge after the use of a pre-emergence herbicide tend to be smaller coming into the spring and should be easier to control.


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Sowing winter crops

Winter Crop Update

Author: George Blackburn 


As October draws to a close, we find ourselves in a far better position from twelve months ago. This time last year the weather was a battle to say the least and the autumn drilling season proved very difficult. We also must take stock on the year that was and 2021 will be remembered as possibly one of the best harvests in living memory. From a rocky start last autumn, crops performed exceptionally well across the board with tillage farmers full of optimism once more. The holy trinity of yield, price and weather all came together to give us all a timely boost. It has reinvigorated the sector and reminded us all why it is we do what we do for a living. Farming is a risky business and feeding the world is becoming a trickier proposition for all sorts of reasons. 2021 has restored a lot of faith and it is nice to be rewarded for our efforts over the past 12 months. Next year may however prove challenging once again especially with fertiliser prices set to increase but farmers are resilient by definition and will put every effort into growing the best quality crops they can for 2022.


Winter Oilseed Rape:

The number of winter rape plantings have increased dramatically this year. Factors such as grass weed issues in cereals, record high prices for rape and a very favourable planting window have all contributed to this. Crops were sown in a timely fashion towards the end of August and early September and have established exceptionally well. Most have already been treated with a pre-emergence herbicide for weeds and a graminicide. The use of hybrid varieties has worked well in the later planting slots. The main concern for many crops at the moment is growth regulation especially in the ranker thicker crops. Aim to apply some metconazole to these crops in the next week to ten days. Pre-emergence herbicide has worked well also, with good chemical uptake in the target weeds. Crops will need to be treated with a fungicide for light leaf spot and some foliar boron when at the 4-8 true leaf stage; probably around mid-November. Crops that weren’t treated with a pre-emergence herbicide or that have grass weed issues will need to be sprayed with kerb or astrokerb when temperatures drop below 12 degrees Celsius. The use of propyzamide and aminopyralid is especially important where fields have been planted to rape to help overcome resistant grass weeds such as wild oats or sterile brome. These fields must receive kerb when temperatures and ground conditions are suitable enough. At current prices, rape looks to be the break crop of choice.


Winter Wheat:

Plantings of winter wheat have increased again on last year with a mixture of early and later sown crops. The excellent returns from wheat in 2021 and the kinder autumn have contributed to this. Again, growers have opted with the tried and tested varieties of Graham and Costello. Both have performed exceptionally well this year with some growers recording record yields. More than one field managed to break the 6-tonne barrier this year showing us that it can be done. Many growers especially on more difficult soils took advantage of favourable conditions in late September. These crops have established excellently with almost 100% germination. Crops sown in late September will be at risk of BYDV and will need an aphicide when at the 3-leaf stage and possibly a follow up treatment approximately a month later. Aphid counts are variable and we are still slightly in the dark as to the relative proportion of resistant aphids in the local population. This year has been milder than last year so far, therefore well timed aphicide applications are a must. We have transform back on the market this autumn with an autumn use label so that should be a big help with no known resistance to this product in the field as yet. The advice must be to err on the side of caution and avoid spraying with a pyrethroid insecticide until at least 3 true leaves are on crops to minimise damage to beneficial insects that feed on aphids in the target population. Later sown crops in marginal conditions will be more at risk of slug damage so growers will need to keep an eye on the emergence of these crops. It is still time enough to sow wheat if conditions allow but be mindful to increase seeding rates as the season moves on.


Winter Barley: 

Winter Barley

Winter Barley plantings are also up as a whole, and many crops have been sown into good quality seedbeds. There is a vast choice of winter barley varieties on the market this year with LG Casting and Valerie two-rows proving popular primarily for their grain quality, with the hybrid six-row Belfry and six-row conventional Kosmos popular in more difficult fields. Joyau a six-row conventional variety with BYDV tolerance was available in limited supply last season and the few crops that were sown performed very well. As a result, there has been an increase in plantings especially in very early slots. It definitely will have a place going forward in rotations. Plant breeding rather than chemistry may be our best weapon against plant pathogens in the future so varieties with more robust genetics for disease and pest resistance will come more to the fore. As with wheat, similar advice applies for aphicide applications. Most crops were treated pre-emergence with a combination of flufenacet and DFF, and this was very important for grass weed control. Any crops not treated will need to get a post emergence treatment of tower and DFF before annual meadow grass tillers. It is essential to treat winter barley for grass as soon as possible in autumn as there is no spring treatment available anymore.


Winter Oats:

winter oats

Winter oat plantings are holding steady with the two main varieties of Isabel and Husky being sown. Oats are generally not sown until after October 10th so there is still plenty of time to plant oats if conditions allow. The above mentioned are both spring varieties planted in the winter so earlier sowing will present more problems than solutions with disease and growth regulation. Aim to plant oats at 12 stone per acre or 200 kg per hectare at this stage of the season to insure a strong plant stand. Isabel is more suited to coastal areas as it has a very good rust resistance profile. Husky is a hardier variety so will prove more suitable to inland areas where winter frost is a higher risk. Winter oats generally do not require an autumn herbicide but crops that may be in fields with annual meadow grass issues can be sprayed pre-emergence with DFF. This is more advisable with Husky than with Isabel.


Further Information: 

To view more articles from our Autumn/Winter Newsletter, please click here. 

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