Wendy Fearon

Grassland

Attention must now be given to those fields which were not sprayed prior to first cut. Grassland herbicides use growth function to kill weeds, therefore peak growth periods should be used for herbicide application. There must be sufficient growth to allow herbicides to be effective and vegetative growth is the key time to apply, as the chemical then gets drawn down into the roots. Herbicides are less successful once plants have progressed to the reproductive stage and have thrown a stem or began to seed. Once weeds are beyond the ideal growth stage for spraying, they should be mowed or topped and allowed to regrow again, and a herbicide applied to the fresh young growth.

To optimise efficacy of any herbicide, recommended water volumes should be observed, even when it means more time spent spraying. It is important to note ragwort plants in their second year are now coming close to flower and should be sprayed immediately as flowering ragwort is poorly controlled. The routine herbicide treatments for this weed are full rate MCPA or 2, 4-D, and they are most active on growing rosettes with reduced activity as the stem starts to extend. They are not clover safe. You can use a mixture of both these products as Nufarm Lupo which allows an increased dose herbicide compared with either alone, with a consequent activity benefit. Forefront is also very effective on ragwort. Stock must be kept off until the weeds have rotted away, which can take up to six weeks.

Buttercups are now ready for treatment. Best results are achieved if sprayed before flowering. ENVY is very effective on both buttercup and dandelions. Envy contains florasulam and fluroxypyr. Together they deliver excellent control of weeds found in pastures which typically get over grazed, receive minimal nitrogen or have poorly competing grass species present. Envy has no manure management restriction and has a short seven-day stock withdrawal period so animals can return quickly. Envy is very safe to grass and won’t hold back its growth. Buttercups are best controlled when they are still green and leafy and before the main flowering period. You will still get control during flowering but for the best effect treat now. Product choice depends very much on which other weeds are being targeted. Where clover is important SPRUCE may be applied to control buttercup.

Potatoes

Where broad –leaved weed control has yet to be completed and the crop has passed the latest timing for Sencorex a reduced rate of Sencorex tank-mixed with Titus will provide a wider weed spectrum of weed control than Titus used alone and can be used on emerged crops up to 25cm high where the label allows .Scutch, other grasses or volunteer cereals are not controlled by the Titus/Sencorex mix. Where these weeds become a problem in coming weeks the graminicide Falcon can be used. Falcon can cause transient yellowing and is therefore not approved for use on seed crops.

As canopies close, the soil surface will tend to remain damper, encouraging slugs onto the soil surface. Timing is critical for effective control, just before the crop meets across the rows. Take advantage of any rainfall by applying pellets just afterwards, as this will bring slugs up onto the soil surface. Potato varieties particularly susceptible to slug damage include Maris Piper, Desiree and Kerrs Pinks.

Blight fungicides move through the plant in three different ways contact, translaminar and systemic. Dithane, Shirlan and Tizca are all contact fungicides. These Products protect only the outer surface of the leaf onto which they are deposited.Translaminar products such as Curzate M, Invader and Ranman Top move into the leaf and redistribute throughout the leaf tissue as it increases in size whilst systemic products such as Zorvec and  Infinito move in through the leaf surface and upwards into the new growth protecting this from infection also. Products that have zoospore activity are the most effective 1^st spray, applied at the rosette stage prior to rapid haulm growth. Shirlan or Tizca will control any zoospores that may be in the soil and provide good protection of the new plant. During the main canopy development phase with the considerable amount of new growth it is essential the product being used is fully systemic to properly protect the new leaves being put on between applications. Later planted crops are higher risk as they produce more new growth between applications than earlier drilled crops, at a time when the level of inoculum in the air is progressively increasing. The way the blight product is applied is as important as the product choice. Make sure nozzle type used is correct to ensure sprayer pressure; droplet size and water applied is as directed on the label. Inspect and calibrate nozzles regularly to maintain performance. Never use any blight product at reduced rates. Do not spray when the leaves are wet as this will significantly increase the likelihood of runoff.

Crop Nutrition

Most spring cereal crops continue to benefit from the recent hot weather with many racing through the growth stages in a matter of days. However the late planting in May and dry weeks since make a challenging combination. With temperatures well above average and daylight hours considerably longer than for a crop drilled in early April, such conditions increase the likelihood of crop stress through too little moisture, or not enough nutrient availability to support the potential rate of growth. As a result many fields are beginning to show variation of colour and growth, and such variation is very difficult to address in a satisfactory way. Manganese (Mn) deficiency is widespread in much of our local soil types, and particularly damaging if not treated. Continuous cereal cropping, ground recently limed and dry soils all increase the likelihood of deficiency.  Symptoms begin with small pale green speckles appearing throughout the leaf and these will progress to turn brown unless treated. Barley is particularly susceptible to Mn deficiency.

A young plant that is growing extremely rapidly is producing a huge amount of new plant tissue each day. This rapid growth is limited only by the availability of nutrients to synthesise biomass, dependant on soil fertility and the plant’s own root development to take up the nutrients. It is at this time therefore when nutrient deficiencies are most likely to appear and in doing so, suppress growth rates.

The application of a broad-spectrum trace-element mix along with key macronutrients during this time is a very useful and beneficial way to supplement the plant’s nutrient requirements during periods when availability does not meet demand, most likely to coincide with phases of rapid growth. Application of a balanced and readily available source of macro & micronutrients that is topping up what is being made available from the soil at this key time will minimise the adverse effects of restricting nutrient availability.  Applying Cereal Plus High N will help your crop overcome these deficiencies.  Cereal Plus High N supplies 250gm Nitrogen, 125gm Sulphur, 93gm Manganese, 38gmMagnesium, 45gm Copper and 15gm Zinc per hectare.Winter cereals are struggling for moisture at present especially winter barley. Disease pressure has been lower than that seen for a long time and fungicides are now complete on winter barley. As temperatures are now a bit lower hopefully this will cause less stress on the flag leaf asT2 applications should now be done on winter wheat crops.

Spring Barley

Dry conditions have held back disease and at present all crops are fairly clean, but in our typically moist climate the likelihood of Rhyncho and Net blotch infections breaking out are inevitable unless controlled in good time.

Even where crops are considered to be clean, controlling Rhyncho early is much more effective than leaving it until it is seen. Once this disease comes into the crop, any eradicant treatment has limited efficacy, will stress the crop and increase the risk of Ramularia infection.

Spring Wheat

The young spring wheat plant isn’t subjected to the same disease burden as the overwintered winter wheat plant, therefore a two-spray programme usually suffices, with the T1 applied at 1^st-2^nd node, GS31-32, and the T2 applied at some point during booting, GS41-49. Whilst a large proportion of these crops are harvested as whole-crop earlier than the conventional combined crop, the feed quality of the harvested crop is very dependant on maximising grain-fill, therefore product choices and rates are similar to those of the winter crop, with significant yield responses to a proper programme.

Lodging Control

Application of Selon at early tillering will have increased tiller and ear numbers and therefore yield potential, but will not have given any reliable strengthening of the straw. Stems that extend rapidly during the stem elongation phase (as has happened this season because of late planting and high temperatures) are more likely to be weaker and so there is a greater risk of lodging especially where the crop is being pushed on with nitrogen. Sonis/Moddus can be used but its cut-off in spring barley is 2^nd node, GS32. Canopy is a very useful alternative, safe to the crop and able to be used right up to and including full flag leaf, GS39.

Selon applied at mid to end of tillering (GS23-30) on spring wheat gives reliable later season lodging control, therefore it is less likely that spring wheat will need a growth regulator towards flag leaf unless the crop is particularly dense.

The extended period of dry weather has allowed farmers to make significant progress on field work. For many growers it has been the earliest end to a spring planting season in a number of years.

Weed control has been difficult to date as crops are growing well but weeds are only just germinating due to the very dry conditions. To minimise the effects of competition on the crop and optimise the level of weed control, herbicide application should be carried out once all weeds have emerged but are still small, and before they begin to compete with the crop for nutrients and light. Carrying out the weed control when they are at the 2-4 leaf stage is much more effective especially on difficult weeds such as fumitory and knotgrass. Whilst chickweed resistant to a wide range of herbicides is commonplace right across the province, the  inclusion of the active arylex into the herbicide tank-mix programmes in recent years has given improved control of  chickweed and other problem weeds including fumitory and sets a new benchmark in terms of weed control in spring barley and wheat. It belongs to a chemical family classified as synthetic auxins, similar to the old hormone chemistry and controls a wide range of broad-leaved weeds including those resistant to the ALS herbicides in most winter and spring cereals, including robust control of fumitory, fat-hen and ALS resistant chickweed. Marketed as ZYPAR, it is available in co-formulation with the active ingredient florasulam and has excellent multiway compatibility along with a very wide range of other pesticides and has no major following crop restrictions. It gives excellent control of a wide range of broad-leaved weeds that includes chickweed, fumitory, fat-hen, groundsel, brassica weeds, and cleavers, but its weakest weed is redshank. Whilst it will control it alone up to 6-leaf, when tank-mixed with ALLY MAX or FOUNDATION it will control redshank right up to flowering.

Temporary nutrient issues

Manganese (Mn) deficiency is widespread in much of our local soil types, and particularly damaging to leaf vigour and yield if not treated. Continuous cereal cropping, ground recently limed and dry soils all increase the likelihood of deficiency.  Symptoms begin with small pale green speckles appearing throughout the leaf and these will progress to turn brown unless treated. Barley is particularly susceptible to Mn deficiency. MAXMAN is a highly concentrated Mn(40%) in a completely soluble chelated nitrate formulation and also supplies 10.8% Nitrogen and 11.4% Sulphur

A young plant that is growing extremely rapidly is producing a huge amount of new plant tissue each day. This rapid growth is limited only by the availability of nutrients to synthesise biomass, dependant on soil fertility and the plant’s own root development to take up the nutrients. It is at this time therefore when nutrient deficiencies are most likely to appear and in doing so, suppress growth rates.

The application of a broad-spectrum trace-element mix along with key macronutrients during this time is a very useful and beneficial way to supplement the plant’s nutrient requirements during periods when availability does not meet demand, most likely to coincide with phases of rapid growth ie. during tillering and as stem extension begins. Application of a balanced and readily available source of macro & micronutrients that is topping up what is being made available from the  soil at this key time will minimise the adverse effects of restricting nutrient availability. CEREAL HIGH N-supplies 250gm N, 125gm S, 38gm Mg, 93gm Mn, 45gm Cu and 15gm Zn per ha

FASTMIX MAGNESIUM PLUS is an alternative product specifically formulated to meet the increased micronutrient demand of cereals and other combinable crops with good yield potential. It is a quick acting foliar fertiliser containing high levels of magnesium and sulphur as well as manganese, zinc and boron, all in a water soluble form and readily available to the plant. It is very compatible in tank-mix with most pesticides and can be applied along with the T1 and T2 fungicide applications. Being a dry formulation, it should be fully dissolved in the tank first and other products added afterwards.

Docks

As thoughts turn to silage, treating dock-ridden leys with Doxstar Pro four weeks before cutting will significantly increase the amount of grass that ends up in the clamp and improve silage quality. Docks have much less feed value than grass and pull down dry matter. Forefront T is the most effective herbicide available to grassland farmers for the control of docks, ragwort, chickweed, thistles, dandelions, nettles and buttercups. It is the longest lasting weed control product in grassland to date with a single well-timed spray giving up to 18 months control so whilst it may appear expensive it really is good value for money. Forefront T may only be applied to grazing ground. Once the established docks have been controlled it is best to keep the problem under control with follow-up treatments every year. This controls new growth of seedling docks that will reappear because all that is required for dormant seeds to germinate is a gap in the sward caused by poaching or tractor marks.

In fertile soils, the dock root system consists of a large tap root with a highly branched mass of smaller fibrous roots. This means what appears to be a small dock plant above ground may in fact be growing from a large rooting system below ground. In order to achieve effective herbicide application docks should be at the rosette stage, with foliage8-10 inches high or across. If grass has been cut or grazed a period of three weeks must occur to allow sufficient regrowth and a suitable target for spraying. If applying Forefront T, Doxstar Pro or Pas.Tor, livestock should be kept out of treated areas for 7 days before grazing and until the foliage of any poisonous weeds has died and become unpalatable. Where clover is important Squire Ultra may be applied in established grass.

Chickweed

There are 2 types of chickweed, common chickweed which has a smooth leaf and is the most commonly found, and mouse-eared chickweed which has a larger leaf than common, with a very hairy surface on the leaf & stem. Chickweed levels have built up very quickly this spring as this weed grows at lower temperatures than grass, and should be treated as soon as possible to avoid choking out the young grass. Similarly, established swards that have been poached by autumn grazing tend to be very open in the early spring and this allows chickweed a chance to become a problem. Chickweed can mature and produce seed in 5-6 weeks hence there can be several generations in a year. Mouse-eared chickweed is very common on many local farms and it is important to note the distinct differences and treatments. Both Envy and Leystar will be used widely on new sown leys this season where clover is not important. As well as controlling both strains of chickweed it will give very good control of dock and thistle.

Where clover is part of the mixture then a clover safe product must be used. Triad is an SU type herbicide that is safe to clover when used correctly. As well as controlling a wide range of BLW’s Triad gives excellent control on chickweed. It will also control seedling docks (not those regrowing from roots), but has no effect on thistles or buttercup. Add Spruce to bring in control of these weeds.

It is extremely difficult to achieve satisfactory control once weeds get beyond the seedling (young plant) stage. Clover content of the sward needs to be higher than is often appreciated. As a rule of thumb there should be 10 plants per square metre at the start of the season. Where plant populations are below this level it is more important to focus on other aspects and be prepared to treat the field as a grass only crop. High levels of nitrogen will significantly reduce clover growth, but by reducing nitrogen inputs overall forage yield will be reduced.

Drilling

The conditions a couple of weeks ago allowed some winter drilling to commence. Unfortunately the turn in the weather has been stop start with herbicide application made very difficult. The only time to control grass weeds in winter barley is the autumn and so it is important to avail of any spray opportunity. Early drilling of winter wheat dramatically increases the risk of take-all following continuous cereals. Therefore a seed treatment is advisable. BYDV is a disease carried by aphids and passed into the crop when they feed on the young plants as they emerge through the ground. Once infected the disease cannot be controlled. Grassy stubbles and volunteer cereal plants act as host plants for aphids. The earlier the crop is drilled, the greater is the risk of infection as the seedling plants are emerging at a time when aphid numbers are high and actively feeding. As the seed treatment REDIGO DETER is no longer available an application of Sumi-Alpha should be applied from the two leaf stage of the crop. Product persistency is very dependent on temperature, increasing as temperatures fall. Applications made whilst temperature remain mild are broken down in 2-3 weeks and therefore most crops will require further applications until aphid feeding ceases as a result of cooler weather.

Slugs

Slugs have thrived throughout the damp summer and damage has already been seen in some oilseed rape crops. All autumn drilled fields should be monitored closely for damage. Loose unconsolidated seedbeds are more prone to damage as slugs can move more easily as moisture conditions dictate. IROXX ferric phosphate slug pellets which have no water issues may be applied at the first sign of damage.

Autumn Herbicides

The key to good herbicide control is early timing, before or soon after emergence of the crop. Residual herbicide product persistency depends very much on damp soils and cooler temperatures. Annual meadow grass is the main target weed in NI as this weed is the most damaging in all cereal crops. Flufenacet is the principle active in autumn herbicide programmes to control AMG giving pre and post-em activity on grass weeds. Flufenacet is available in mixtures such as CRYSTAL and NUCLEUS. Nucleus which was launched in 2018, is a combination of flufenacet and diflufenican, providing broad spectrum weed control in a very cost effective package.  Complete control of autumn emerging weeds including annual meadow grass can be achieved for as little as £13.00 /acre.    Crystal which contains pendimethalin and flufenacetgives improved control of brome species in wheat and barley but groundsel in particular will still need to be treated in the spring.

The mix of sunshine and rain over the last couple of weeks has provided a period of good growth in all crops, but with this comes a ramping up of weed and disease activity. The heavy showers in recent days have encouraged even germination of weed populations in all spring cereal crops, and if not already sprayed for these, should be done so as a priority in coming days, as performance will fall off rapidly when the weeds become larger and the crop canopy closes, shading out the weeds underneath. As a result of a near ideal balance of heat and rain since planting, all spring crops are now well established and well into the tillering growth stage. Most are clean and canopy cover is consistent right across fields.

Chlorothalonil revocation update

Following the announcement of its revocation earlier in the year, the use up period for chlorothalonil containing products has been announced. Products may be sold up to 20^th November this year, and growers will have to the 20^th May 2020 to use or dispose of stock. Whilst the fact growers will have the active for much of next season is better news than might have been expected, longer term its loss will impact significantly on crop protection programmes in terms of efficacy and resistance management.

Disease Control

Spring Barley

At the moment crops look pretty clean, so in most cases the lower end of the dose range will suffice, but with disease risk closely linked to heat and moisture, decisions on rates are the ultimate in-field decision and should be tailored to the disease pressure in each field.

Even where crops are considered to be clean, controlling Rhyncho early is much more effective than leaving it until it is seen. Once infection has come in, any eradicant treatment has limited efficacy, and the infection will stress the crop, increasing the risk of Ramularia infection. The T1 application should be applied at the end of tillering to the start of stem extension, GS24-31.

The T2 timing should be aimed to continue control of Rhyncho and Net Blotch, but also timed to maximise control of Ramularia. Flowering and senescence are major triggers of symptoms, but other stresses also play a part including bursts of sunshine, diurnal temperature fluctuations, and the presence of other foliar diseases. This spray needs to be on ahead of Ramularia symptoms appearing on final leaves one and two and persist for long enough to keep the crop green well in to grain fill. The best compromise timing for this is booting to very early ear emergence, GS41-49.

Options for T1 are based around core triazoles such as prothio, epoxi and cyproconazole. Prothioconazole remains the strongest performing triazole but epoxiconazole mixes are equally effective options, ensuring the various strains of disease are exposed to as many different actives throughout the programme as possible. Strobilurins improve the performance of the triazole partner, improving Rhyncho, Net Blotch and Rust activity. SDHIs will also give very good broad spectrum disease control, but factoring in cost effectiveness, are a better fit at the more responsive T2 timing.

Spring Wheat

The young spring wheat plant isn’t subjected to the same disease burden as the overwintered winter wheat plant, therefore a two-spray programme usually suffices, with the T1 applied at 1^st-2^nd node, GS31-31, and the T2 applied at some point during booting, GS41-49. Whilst a large proportion of these crops are harvested as whole-crop earlier than the conventional combined crop, the feed quality of the harvested crop is very dependant on maximising grain-fill, therefore product choices and rates are similar to those of the winter crop, with significant yield responses to a proper programme.

Spring Oats

Powdery Mildew and Crown Rust are the most damaging diseases in this crop. OPUS TEAM & COMET in mixture is the strongest combination in terms of controlling both these diseases and therefore yield improvement. Fenpropimorph (an active in OPUS TEAM) is extremely effective in terms of Powdery Mildew control, and the addition of COMET (a strobilurin) gives unrivalled Crown Rust control.

A single application of fungicide should be applied at 1^st – 2^nd node, (GS31-32) eradicating any Mildew and Rust already present, and providing persistency right through to harvest.

Lodging Control

Spring Barley

Application of SELON at early tillering will have increased tiller and ear numbers and therefore yield potential, but will not have given any reliable strengthening of the straw. Stems that extend rapidly during the stem elongation phase (as is likely to happen this season because of late planting, high temperatures and soil moisture at present) are more likely to be weaker and so there is a greater risk of lodging especially where the crop is being pushed on with nitrogen. SONIS can be used but its cut-off in spring barley is 2^nd node, GS32. CANOPY is a very useful alternative, safe to the crop and able to be used right up to and including full flag leaf, GS39. If this timing has past, CERONE can be applied up to before awns visible, GS45.

Spring Wheat

Because the application of SELON at mid to end of tillering (GS23-30) does give reliable later season lodging control in wheat, it is less likely than spring barley that spring wheat will need a growth regulator towards flag leaf unless the crop is particularly dense. If the crop still looks very rank and at risk of lodging as the stem elongates, apply CERONE or CANOPY, as the flag leaf is emerging.

Spring Oats

The optimum timing for treating spring oats is with SELON at 2^nd node, GS32. However if the oats remain at risk of lodging, a follow up treatment of CANOPY can be applied during flag leaf emergence

Spring Cereals

The much more pleasant milder night-time temperatures have seen a welcome burst of new growth in all crops. All spring crops have now brairded and without the more usual effects of waterlogging seen in other years, are looking very well. Although weeds are also emerging fast as a result of last weeks rain, be sure all are well through before spraying. Watch too the size of the annual meadow grass if this weed is also to be controlled – efficacy falls off rapidly once it begins to tiller.

A well timed application of SELON will encourage tiller numbers and tiller survival. This treatment must be well timed to maximise its effect, optimum timing for barley is from the 2 expanded leaf stage to beginning of tillering, GS12–21; in wheat the optimum timing is slightly later, 5 leaf to mid tillering, GS15-24. Many crops will have now passed through these growth stages. It is important to note that this season aphid numbers are the highest I have seen for a very long time and it would be advisable to apply an aphicide to control the spread of BYDV.

To minimise the effects of competition on the crop and optimise the level of weed control, herbicide application should be carried out once all weeds have emerged but are still small, and before they begin to compete with the crop for nutrients and light. Carrying out the weed control when they are at the 2-4 leaf stage is much more effective especially on difficult weeds such as fumitory and knotgrass, rather than delaying to coincide with the 1^st fungicide application.

Broad leaved weeds resistant to particular groups of herbicides in NI is not a new problem – chickweed resistant to herbicides such as ALLY has been widespread throughout the province for some years. Sulfonyl urea (SU) herbicides such as metsulfuron have a single mode of activity, blocking the production in many BLW of a key enzyme, acetolactate synthase. Products that use this mode of activity are known as ALS inhibiting herbicides and include the SU chemistry. As well as chickweed, mayweed and poppy have also developed widespread ALS resistance. This particular resistance problem has been managed by including herbicides into the tank-mix with different modes of activity to maintain good weed control.

In NI spring cereals ZYPAR will give excellent control of a wide range of weeds that includes chickweed, fumitory, fat-hen, groundsel, brassica weeds, and cleavers. Its one relative weakness is redshank. Whilst it will control it to 6-leaf, it should be tank-mixed with another herbicide to ensure redshank right up to flowering is satisfactorily controlled. ALLY MAX and FOUNDATION are excellent tank-mix partners for this purpose.

Temporary nutrient issues

Manganese (Mn) deficiency is widespread in much of our local soil types, and particularly damaging to leaf vigour and yield if not treated. Continuous cereal cropping, ground recently limed and dry soils all increase the likelihood of deficiency. Symptoms begin with small pale green speckles appearing throughout the leaf and these will progress to turn brown unless treated. Barley is particularly susceptible to Mn deficiency. MAXMAN is a highly concentrated Mn(40%) in a completely soluble chelated nitrate formulation and also supplies 10.8% Nitrogen and 11.4% Sulphur

A young plant that is growing extremely rapidly is producing a huge amount of new plant tissue each day. This rapid growth is limited only by the availability of nutrients to synthesise biomass, dependant on soil fertility and the plant’s own root development to take up the nutrients. It is at this time therefore when nutrient deficiencies are most likely to appear and in doing so, suppress growth rates.

The application of a broad-spectrum trace-element mix along with key macronutrients during this time is a very useful and beneficial way to supplement the plant’s nutrient requirements during periods when availability does not meet demand, most likely to coincide with phases of rapid growth ie. during tillering and as stem extension begins. Application of a balanced and readily available source of macro & micronutrients that is topping up what is being made available from the soil at this key time will minimise the adverse effects of restricting nutrient availability. CEREAL HIGH N-supplies 250gm N, 125gm S, 38gm Mg, 93gm Mn, 45gm Cu and 15gm Zn per ha

FASTMIX MAGNESIUM PLUS is an alternative product specifically formulated to meet the increased micronutrient demand of cereals and other combinable crops with good yield potential. It is a quick acting foliar fertiliser containing high levels of magnesium and sulphur as well as manganese, zinc and boron, all in a water soluble form and readily available to the plant. It is very compatible in tank-mix with most pesticides and can be applied along with the T1 and T2 fungicide applications. Being a dry formulation, it should be fully dissolved in the tank first and other products added afterwards.

Winter Cereals

Winter cereals have greened up well and are now racing through the growth stages. Awns are now out on all winter barley crops with both T2 application and growth regulator applications complete. Winter wheat crops which have not yet received T2 should be treated as soon as possible along with the growth regulator if required.

Winter Cereals

Winter cereal crops are moving rapidly through their growth stages. As a result of the predominantly dry April and better timed spray treatments than many other years, the wet weather diseases, Septoria and Rhyncho remain lower down the plants, well controlled by the T1 application. Dry weather diseases have been more problematic this year, with Net Blotch, mildew and Ramularia appearing in barley and Yellow Rust and Mildew in wheat.

As awns appear in barley and the flag leaf emerges in wheat, the T2 fungicide timing is fast approaching.

Properly protecting the top three leaves and ear at T2 is critical to yield and profit – foliar disease not controlled effectively at this time will hasten the senescence of these leaves during grain filling, and therefore impact adversely on yield and grain quality. This treatment will extend canopy duration therefore increasing the amount of starch produced for grain filling, and increase grain storage capacity leading to higher thousand grain weight (TGW).

Winter Barley

Correct timing of fungicide applications is critical to optimizing activity and product performance. The T2 treatment should be applied from flag leaf sheath extending, through booting to first awns visible, GS41-49. As well as protecting against Rhyncho, this treatment also needs to protect the plant against Ramularia, Brown Rust and Net Blotch through to the end of the season. Awns contribute equally to yield and it is important to keep them free of disease also.

For crops with good yield potential, the inclusion of SHDI along with triazole and multi-site is very much the norm now, ensuring persistency of the treatment right through to ripening. Best options include AYLORA or CONCORDE mixed with MOBIUS/MANTRA/RUBRIC and the multisite chlorothalonil. Good practice would be to use a different SHDI/triazole combination now to that already used at T1. Where a crop with lower yield potential discourages their use, non SDHI chemistry using triazole/strobilurin/morpholine mixes are also robust options eg OPUS-TEAM, MANTRA or MOBIUS. As a result of its resistance to triazoles and the SDHIs increasing, chlorothalonil should now be considered an essential component of all T2 treatments helping the control of Ramularia.

Winter Wheat

In wheat the T2 should be applied during the emergence of the flag leaf, GS37-39. Of all treatments, this flag leaf timing is the most responsive to yield and therefore products used should reflect this. Against a background of Septoria being present in all crops and significantly reduced kickback activity from core chemistry, the T2 timing is critical to ensure effective protectant performance.

Managing resistance and maintaining reliable disease control now means using a range of different actives over the course of the growing season

It is good practise to use different actives from within the same chemical group at the different spray timings. Where possible, use a different SDHI at T2 to that used at T1, and likewise use different triazoles over the course of the season to give the widest possible activity across the different strains of fungi of all diseases.

Because it provides multiple modes of activity acting preventatively on Septoria and has no known resistant strains to the disease, chlorothalonil should also be included in all well timed T2 programmes to provide some control of those strains now showing resistance to triazoles and even SDHIs. In crops susceptible to lodging a plant growth regulator should be applied at this time.

Docks

As thoughts turn to silage, treating dock-ridden leys with DOXSTAR PRO four weeks before cutting will significantly increase the amount of grass that ends up in the clamp and improve silage quality. Docks have much less feed value than grass and pull down dry matter.  FOREFRONT T is the most effective herbicide available to grassland farmers for the control of docks, ragwort, chickweed, thistles, dandelions, nettles and buttercups.  It is the longest lasting weed control product in grassland to date with a single well timed spray giving up to 18 months control so whilst it may appear expensive it really is good value for money. FOREFRONT T may only be applied to grazing ground.  However PASTUREPACK launched last season by Nufarm will cover a similar range of weeds and may be applied on silage ground. Once the established docks have been controlled it is best to keep the problem under control with follow-up treatments every year.  This controls new growth of seedling docks that appear as all that is required for dormant seeds to germinate is a gap in the sward caused by poaching or tractor marks.

In fertile soils, the dock root system consists of a large tap root with a highly branched mass of smaller fibrous roots. This means what appears to be a small dock plant above ground may in fact be growing from a large rooting system below ground. In order to achieve effective herbicide application docks should be at the rosette stage, with foliage8-10 inches high or across. If grass has been cut or grazed a period of three weeks must occur to allow sufficient regrowth and a suitable target for spraying. If applying FOREFRONT T, DOXSTAR PRO or PAS.TOR, livestock should be kept out of treated areas for 7 days before grazing and until the foliage of any poisonous weeds has died and become unpalatable. Where clover is important SQUIRE may be applied in establishes grass.

Chickweed

There are 2 types of chickweed, common chickweed which has a smooth leaf and is the most commonly found, and mouse-eared chickweed which has a larger leaf than common, with a very hairy surface on the leaf & stem. Chickweed levels have built up very quickly this spring as this weed grows at lower temperatures than grass, and should be treated as soon as possible to avoid choking out the young grass. Similarly, established swards that have been poached by autumn grazing tend to be very open in the early spring and this allows chickweed a chance to become a problem. Chickweed can mature and produce seed in 5-6 weeks hence there can be several generations in a year. Mouse-eared chickweed is very common on many local farms and it is important to note the distinct differences and treatments.Both ENVY andLEYSTAR will be used widely on new sown leys this season where clover is not important. As well as controlling both strains of chickweed it will give very good control of dock and thistle.

DOXSTAR applied at 1lt/ha, will control both types of chickweed in established swards. Neither will check the growth of immature grass plants and are not clover safe. Where clover is part of the mixture then a clover safe product must be used. TRIAD is an SU type herbicide that is safe to clover when used correctly. As well as controlling a wide range of BLW’s TRIAD gives excellent control on chickweed. It will also control seedling docks (not those regrowing from roots), but has no effect on thistles or buttercup. Add SPRUCE to bring in control of these weeds.

It is extremely difficult to achieve satisfactory control once weeds get beyond the seedling (young plant) stage. Clover content of the sward needs to be higher than is often appreciated. As a rule of thumb there should be 10 plants per square metre at the start of the season. Where plant populations are below this level it is more important to focus on other aspects and be prepared to treat the field as a grass only crop. High levels of nitrogen will significantly reduce clover growth, but by reducing nitrogen inputs overall forage yield will be reduced.

The extremely wet and windy weather over the last couple of weeks has delayed fertiliser and spray applications. Crops have begun looking for nitrogen and as daylight hours are longer it is essential to apply fertiliser onto crops as soon as ground conditions allow. The amounts of P&K at the target index 2 must be maintained and it is important to take into consideration the offtake in yield of grain when planning fertiliser applications. As most of our straw is removed an NPK fertiliser should be applied in accordance with the RB209 taking into consideration the use of organic manures. Cereals are becoming more responsive to sulphur as atmospheric deposition of sulphur declines. Where deficiency has been recognised or is expected 25-50kgSO3/ha as a sulphate should be applied in early spring before the start of stem extension.

Fastmix Magnesium Plus contains the following available nutrients- magnesium, sulphur, zinc and manganese. This product is rapidly absorbed by the plant quickly correcting deficiencies. Fastmix has been specially developed to meet the micronutrient demand of cereals and other leafy crops with a high manganese demand in an ideal combination with magnesium and sulphur.  It is a cost efficient nutrient application technique for Mg, S, Mn and Zn without additional costs, if combined with the regular crop protection program.  It also helps activate nitrogen into the plant to enhance seed development and transference of sugars throughout the plant, sulphur is one of 17 elements essential for crop growth. Although sulphur is considered a secondary nutrient it is often referred to as the fourth major nutrient ranking just below NPK. Sulphur deficiency can often be mistaken as nitrogen deficiency. The pale yellow symptoms of sulphur deficiency often appear on the younger or uppermost leaves whilst nitrogen deficiency initially appears on the older leaves.

Crops lacking sulphur appear stunted, spindly and thin stemmed and maturity in cereal grains is delayed. When deficient, Mg is transferred in the plant from older to new tissue. As a result, deficiency symptoms occur first in older leaves. Tissue between the veins becomes light green to whitish in colour. In cereals this leads to striping between veins that may be intermittent rather than continuous. With severe deficiencies, purple colouration may follow. I have observed quite a lot of mildew especially on winter barley crops across the province over the last couple of weeks. I am advising a T0 fungicide treatment as rhynchosporium levels have also become quite high. It is also important to observe the winter wheat varieties when considering a T0 bearing in mind the low resistance some varieties have to mildew.