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Soil structure is a much neglected aspect of grassland management. Water availability can be a prime limiting factor in grass growth. Either too little or too much cause’s restriction in output and corrective action may be needed. An assessment of the soil type, structure, should be made in order to identify and rectify any problems at an early stage. It is important to maintain a good firm, well-drained soil. Land should be sub soiled if compaction occurs and gateways and bare areas should be patched up. Heavy machinery should not be used in wet or waterlogged fields. When working the land continuously using heavy forage equipment, try and use different wheeling’s to avoid localised compaction, which is difficult to correct. It is also important not to allow poaching by grazing stock in wet conditions.

Fields should be tested regularly to check the pH and nutrient status of the soil. Although this may seem costly it is money well spent .It is advisable for optimum production and should be carried out at least every 3 years. The optimum pH for good grass and clover growth is 6-6.5.If the pH falls below 6, lime should be applied. If the pH is not corrected, the fertilizer applied will not give their optimum performance.

All growing crops require nutrients throughout the growing season. Nitrogen is the most important nutrient and is responsible for protein production as well as producing chlorophyll within the grass. Phosphate is important for the development of roots and tiller survival. Potash is involved in a number of functions including protein production and the efficiency of photosynthesis. Too much potash will suppress the uptake of magnesium in cattle and sheep causing “grass staggers” (hypomagnesaemia).It is therefore important that potash is not applied before spring grazing. The amount of potash required is determined by soil type; clay soils having greater available soil reserves than sandy soils.

It is now time to assess the presence of weeds in the sward and choose the correct product to control the problem.

Cow parsley is becoming an increasing problem weed it will grow in sunny to semi-shaded locations in fields and at the edges of hedgerows and woodland. It is a particularly common sight by the roadside. It is sufficiently common and fast-growing to be considered a nuisance weed. Cow parsley’s ability to grow rapidly through rhizomes and to produce large quantities of seeds in a single growing season has made it an invasive species in many areas of Northern Ireland. GRAZON PRO will give very good control of cow parsley.

DOCKS

Although grass growth has been reasonably good and weeds seem to be at their optimum timing I would hold off spraying until day and night conditions are consistent. Hopefully conditions over the next few weeks will provide an opportunity to get a start made to weed control. As thoughts turn to silaging, treating dock-ridden leys with DOXSTARPRO 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.

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.

No dock spray will give complete control with a single application – effective dock control requires a programmed approach, follow-up applications to deal with docks and germinating seed docks not controlled in the first treatment. Long term control can only be achieved using a sequence of applications of a translocated herbicide because of the potential for regrowth both from roots and the seed bank built up in the ground over the years.

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, DOXSTARPRO or PASTOR, 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 ULTRAmay be applied.

THISTLE

The Creeping Thistle is a perennial which grows from seed or from root sections in the soil.  Once established the root mass can be greater than the plant above ground hence competing effectively with the grass. The Spear (Buck or Scotch) thistle is a biennial plant which grows from seed. In the first year it produces a small rosette, and then in the second year the plant can grow to over 1 metre in diameter and height. Thistles are common on older swards, those low in phosphate and nitrogen but high in potash. These conditions are more typical of beef and sheep farms. As with the Docks, good chemical control requires spraying at the right stage i.e. when the majority of plants are at the full rosette stage, just as stem elongation begins. However because of the wider range of growth stages of a population of thistles at a point in time, not all will be at the right stage at the right time. Topping thistles stops seed spread but not root spread.THISTLEX may be applied which will give a high degree of root kill or alternatively LUPO or MCPA may be applied which will give good control of top growth but limited root kill. Where clover is an important constituent of the sward SPRUCE should be applied.

RAGWORT

Never before has ragwort been such a problem on Northern   Ireland farms, especially in lower fertility situations. Ragwort contains alkaloids which are poisonous to all livestock. It is a biennial plant i.e. it grows from seed the first season to produce a rosette plant, and then the following season it produces a flowering stem, seeds, and then dies. Each plant can produce up to 150,000 seed with a 70% germination rate and seeds can remain dormant in the soil for up to 20 years.

Whilst ragwort is unpalatable when it is green, it becomes extremely palatable once sprayed or ensiled. First year plants are now at the rosette stage, the ideal growth stage for effective control. A single application of weed killer is unlikely to completely eliminate a ragwort infestation and a follow up treatment will have to be made. When the plant is already in flower treatment is less effective and seeds will already have been set for the following year.LUPO may be applied as part of a programmed approach. FOREFRONTT is also very effective on ragwort.

CHICKWEED

There are 2 types of chickweed, common chickweed which is the most commonly found type, with a smooth leaf 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.

PASTOR applied at 2lt/ha, and DOXSTAR applied at 1lt/ha, will control both types of chickweed. They are reliable when used in cool, early spring conditions and neither will check the growth of immature grass plants but are not clover safe.

CLOVER SWARDS

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 also.

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.

SILAGE

To ensure a well fermented silage sufficient fertiliser must be applied at the correct time for intended cutting dates. On average allow one day’s growth for each 2-3 units of nitrogen between application and cutting. The younger the grasses the higher the feed value but the lower its yield. In general aim to cut before 50% of the ears have emerged to gain as much yield as possible. Short chopping speeds up fermentation and aids consolidation ensuring not to cut too short as long fibre is required for rumen function. Where conditions allow fast wilting in good weather this will increase the concentration of sugars and reduce effluent production. Hopefully the weather will be kind and some quality silage will be made in the coming weeks.

With temperatures rising, days getting longer and top dressings kicking in, crops are starting to come away, especially those on drier soils. Soil temperatures have not dropped as low as usual with the milder winter and therefore the early start to growth comes as no surprise and is encouraging in terms of building yield. Unlike autumn 2012, autumn 2013 allowed most of the winter barley crop and a considerable share of winter wheat to receive a herbicide treatment in the autumn with mixtures of Crystal and Sempra widely used. Performance has been excellent and therefore fewer crops are requiring treatment this spring.

Winter Barley GS30 – GS31

All crops have completed tillering, with the most forward fields past 1^st node, GS31. Most are looking well considering the wet conditions over the winter. There are good plant counts and tiller numbers, but the mild winter means disease is already well established on these young plants with Rhyncho, mildew and net blotch showing in all.  Rhyncho remains the most damaging disease of barley, seriously damaging yield potential if not controlled quickly and effectively.

Winter Wheat GS22 – GS30

Growth stages vary widely depending on drilling date but most are at various stages of tillering. Most have good plant numbers but some fields have suffered from poor seedbeds, waterlogging, slug and leatherjacket damage. As temperatures rise slugs and leatherjackets are still a threat to more backward crops and should be treated if any new damage is seen. Septoria is established in all crops but particularly so in earlier drilled fields.

Disease Control

Timing of fungicide applications and rates used are every bit as critical as product choice to achieve the maximum potential response. To ensure the main disease programme persists right through to ripening, it is essential farmers do not apply their main T1 fungicide application before about the middle of April, with the T2 and T3 applications following at 4-5week intervals, ie mid-May and mid-June. This T1 timing should coincide with the beginning of stem extension between 1^st and 2^nd node, GS31-32.

Holding the T1 timing to GS31-32 should ensure T2 in barley and T2 & T3 in wheat be optimally timed to avoid extended gaps, maintaining persistency right up to and during senescence. Where a crop has not received a T0 treatment product rates at T1 will need to be increased to take account of this.

Since their introduction, fungicide programmes containing SDHIs, or succinate dehydrogenase inhibitors have consistently out-performed triazole only programmes. These are the newest family of chemistry available to cereal growers and now considered the mainstay of disease control programmes. They work by inhibiting fungal respiration and are more effective at controlling a range of diseases than older products, particularly as the performance of triazoles continue to decline each year. However SDHIs only have this single mode of action and therefore resistance and the associated breakdown in control is a very real threat to these products. To try and prevent resistance building up against the SDHIs, they must be used only twice in a season and in conjunction with another fungicide, such as a triazole, with a different mode of action.

The first SDHI launched was boscalid from BASF back in 2004. After a gap of some years then a second generation of SDHIs have come to the market in recent years, with Syngenta’s izopyrazam launched in 2010, Bayer’s bixafen launched in 2011, and BASF’s fluxapyroxad in 2012. Last year DuPont launched penthiopyrad as a straight called VERTISAN and also as a mix with chlorothalonil called TREORIS and AYLORA in March 2013.

Of the SDHI products available, penthiopyrad (in AYLORA) is the most effective performer on both Septoria and Rhyncho, being as strong preventatively as bixafen and fluxapyroxad but stronger curatively. Boscalid (in WHISTLE/CHORD) remains the strongest active available to control Eyespot and therefore the best option for use on wheat at T1.

Prothioconazole and epoxiconazole continue to be the strongest triazoles available in wheat but are now consistently outperformed by the co-form products PROSARO and BRUTUS every time. Prothioconazole on the other hand is the clear leader controlling Rhyncho in barley.

Whilst the strobilurins now contribute little to Septoria control, they still perform well on Rusts and the late ear diseases on wheat, and on Rhyncho and net blotch on barley. Pyraclostrobin (COMET) is the strongest of the strobilurins and an excellent mixer with most other fungicides.

Chlorothalonil remains a strong Septoria protectant as well as its multi-site activity being essential to manage resistance. Limited to two applications, best timing continues to be T1 and T2.

The T1 treatment in oats should be applied at the same time as the growth regulator. Whilst traditionally a single fungicide program was often used on this crop, a 2-spray program consistently outperforms a single spray in terms of yield, bushel-weight and profitability.

CAPALO is the strongest T1 treatment available in oats, giving excellent curative activity on Crown Rust and Mildew when applied at 1^st–2^nd node (GS31-32), and is very persistent keeping new growth clean right up to full flag leaf (GS39) when the T2 is applied.

Weed Control

While most crops received a herbicide treatment in the autumn, for those still to be treated, control of Annual Meadow Grass (AMG) is the most pressing issue. OTHELLO is an excellent option for AMG in wheat into the spring, however there is no similar late option for barley. None of the autumn products will control AMG beyond the mid tillering stage, yet they are the only AMG options for barley. Therefore any barley not yet sprayed must be done as a matter of urgency if satisfactory control of AMG is to be achieved.Note that OTHELLO will only control AMG that has already emerged; unlike the autumn products it has no pre-emergent activity.

The incidence of brome infestations is becoming more common. Where this weed has become a problem, a sequenced approach is the only really effective way of controlling the weed, ie an autumn treatment followed up with a spring treatment. CRYSTAL at 4lt/ha in the autumn is the first part, and can be applied to wheat and barley. The follow-up then in the spring is BROADWAY STAR but note this product can only be used on wheat. There is no follow-up product available for barley and therefore in a severe infestation situation, only wheat allows effective control.To avoid crop damage, do not spray any crop under stress. Note that performance of some wild oat/brome herbicides can be adversely affected by other herbicides used on the crop. To avoid these antagonisms, a minimum time interval must elapse between application of the BLW herbicide application and this application.

Growth regulation

When applied before 1^st node, GS31, application of certain chlormequat growth regulators can significantly increase tiller numbers. Chlormequat works by suppressing apical dominance, ie main stem development. In doing so it diverts the plant’s resources into producing and supporting more tillers. Particularly in wheat but in barley also, more tillers will go a long way towards compensating for low plant counts, ultimately increasing yield.

Correct timing is critical to maximise this effect. The earlier it is applied during tillering the greater the tiller effect, but note early application to increase tiller numbers will also reduce its effect on lodging. Application of a chlormequat based growth regulator often goes on with a T1 fungicide application sometime around 1^st-2^nd node, GS31-32. At this timing it is too late to affect tiller numbers and survival but will maximise the stem stiffening effect.

Early application will also increase root growth and so reduce stem-base lodging. Stem-base lodging is where the plant folds over at the soil surface as a result of poor anchorage in the soil, and is caused by poor root ball development, more likely when the seedling develops in wet soils that limit root development. All winter crops have rooted very shallow this season as a result of the persistently wet conditions and therefore stem-base lodging is likely to be a significant problem later this season.

The rates of use, label timings and tank-mix flexibility for SELON are identical to ADJUST. SELON can be tank-mixed with the herbicide and where the crop has begun to tiller, should be applied now.

Nutrient Deficiency

A combination of waterlogged soils, plants already suffering from restricted nutrient uptake and plants now trying to grow is showing up Mn deficiency in many barley crops. Continuous cereal ground and ground recently limed is most prone to deficiency. Symptoms begin with small pale green speckles appearing throughout the leaf and these will progress to turn brown unless treated.

As soon as the ground allows, Mn deficiency should be addressed and applied as soon possible along with the SELON application to increase tiller numbers.

Copper deficiency often accompanies Mn deficiency – its symptoms are complete browning of the leaf tip especially the youngest leaves, and apparent wilting of the plant. Treatment will be most effective if treated immediately symptoms are seen.

With air quality significantly improving over the last two decades, the most important source of sulphur to the soil coming from the pollutant gas sulphur dioxide has also reduced significantly. Whilst its deficiency is now being recognised  and corrected on grassland through the application of high sulphur compound fertilisers, its impact in cereal crops in NI  has by and large been misidentified or overlooked. After nitrogen, phosphate and potash, sulphur is the next most important element required by all crops, used to make essential sulphur containing amino acids and proteins in all plants. Soil sulphur is easily leached especially from light to medium soils, making shallow-rooting plants particularly vulnerable to deficiency. Deficiency causes paling in the cereal plant, caused by a reduction in chlorophyll production and even in the absence of any symptoms, decreased efficiency of nitrogen utilisation. Whilst often mistaken for lack of nitrogen, sulphur is not very mobile within the crop and therefore deficiency is most pronounced on the younger leaves; the opposite to nitrogen deficiency which affects the oldest leaves first. Crops of both wheat and barley with high yield potential are particularly responsive to one to two applications of foliar sulphur at the timings of rapid growth.

Welcome to the first crop crack of 2014.

Growers should be making the best of this quieter time to assess the performance of last season’s crops and plan for the incoming season. Fields which are going to be cropped early should be identified and an up to date soil analysis carried out. Routine machinery maintenance should be carried out at this time of year to prevent unnecessary breakdowns during the busy season. All sprayers should be thoroughly checked to ensure all pipes and pumps are fully functional.

HEDGEROW CONTROL

Season long control of grasses and most broad-leaved weeds is possible by applying Kerb Granules at this time. Kerb is a pre- and post-emergence residual herbicide for the control of annual and perennial grasses and a wide range of other weeds in farm and commercial forestry, ornamental plantings and recreation areas.   Propyzamid, the active ingredient in Kerb, works by inhibiting cell division, disrupting the growth process and leading to eventual death of the plant.  Kerb can be applied to all soil types, therefore allowing its use in many areas where weed control is needed.  Kerb is the ideal herbicide for forestry and woodland (including farm forestry), ornamental shrubberies and rose beds, hedges, fence lines and gravel pathways.  Kerb requires soil moisture for root uptake to take place. Kerb Granules are mobile in the soil profile and therefore the best results will be achieved when applying in cooler conditions, usually between October and February. If warm, dry conditions prevail after application then weed control may be reduced. Although Kerb can be applied in all weather conditions, application on top of snow, or to severely frozen ground should be avoided if there is any risk of surface run-off.

VERMIN CONTROL

Farm buildings should be checked and sealed to prevent access by rats and mice who will be seeking shelter. Make buildings as impenetrable as possible by sealing off possible entry points, and set traps to gauge whether any vermin have managed to already gain access to buildings.

Storm Secure bait should be placed close to runs and holes where rats are active. If the bait is covered with boards or lengths of pipe it gives the rat a feeling of security when feeding and also protects the bait from the weather and hidden from other animals, children or livestock. Ideally use a specially designed bait box.

The cereal acreage in the ground to date  is the highest seen for some time but the  recent heavy rainfall has slowed down winter wheat drilling and autumn herbicide application.  Slug populations were high throughout the summer and remain so, posing a threat to all crops especially with the current mild damp conditions.  Early drilling of winter wheat dramatically increases the risk of take-all following cereal situations. 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.  If a seed treatment has not been applied an application of Sumi-Alpha should be applied from the two leaf stage of the crop.

Annual meadow grass is the main target weed in NI as this weed is the most damaging to yield in all cereal crops. The key to good herbicide control is early timing –  before or soon after emergence of the crop.  This season with the dry warm conditions pre-em products have not performed as well as expected.  Residual herbicide product persistency depends very much on damp soils and cooler temperatures. Scorch has also been an issue with high soil and air temperatures in some crops this autumn.

The last two seasons have enabled us to learn more about the autumn herbicides when used beyond their recommended timing.  After two very wet autumns, much of the flufenacet in CRYSTAL and chlortoluron(CTU) in BUCKLER was applied well after the optimum timing. Crystal applied onto barley crops at the 3-4 lt rate per ha performed extremely well on well tillered annual meadow grass (AMG).  The inclusion of BUCKLER in the mix will control larger AMG but there is varietal restriction.  Sempra has been widely used this autumn in mix with Crystal to strengthen the spectrum of BLW control where weeds are through the ground.  Most of the herbicides that are effective on AMG are not safe on oats, making grass weed control in this crop particularly difficult.  In recent years LEXUS CLASS has been the principle product used and does a reasonable job when conditions and timings are optimal.  SUMIMAX is now another alternative but is an off label approval(EAMU) for use on winter oats.  It gives improved AMG activity over LEXUS CLASS and has excellent broad spectrum BLW activity including groundsel and fumitory but must be used pre-emergence of the crop.  Othello will be widely used again this spring onto winter wheat crops. In known deficient soils, manganese should be applied during November. Treatment of the condition before deficiency symptoms are seen will mean stronger healthier plants going through to spring.

There have been several blight warnings recently and it is important not to stretch spray intervals at this critical time. A fair acreage of land has been reseeded this season and combines have been busy in many areas over recent weeks but this week it has been a bit stop start.  I would urge all farmers to assess both land intended for reseeding and winter cereals to monitor for slugs as numbers are greater than they have been for some years.  Treated seed is a priority if slugs are present. I would like to impress on you the need to carry out soil samples at this time to ensure all nutrients will be readily available to the growing crop.

Grassland Weed Control

Ragwort is appearing in many grass situations at present and is becoming a greater problem especially in lower fertility situations; it is an ‘injurious weed’ and is not permitted to grow unchecked.  Ragwort is a biennial plant i.e. it grows from seed the first season to produce a rosette plant and then the following season it will produce a flowering stem, produce seed then die.  Ragwort contains alkaloids which are poisonous to all livestock except sheep. Each plant can produce up to 150,000 seed with a 70% germination rate and seeds can remain dormant in the soil for up to 20 years. Treatment of plants, which are at the rosette stage now, can be very effective and an autumn application allows a check on the efficacy of the treatment to be made in early spring before allocating fields for silage or hay.  Autumn is a good time to spray as the grass growth slows down and grass utilization and withdrawal periods are not as critical as they can be in the spring time when stock are turned out. Whilst ragwort is unpalatable when it is green it becomes extremely palatable once sprayed. It is important to remove as much of the root as possible; ragwort can regenerate like docks from its root fragments.  A single application of weed killer is unlikely to completely eliminate a ragwort infestation due to overlapping generations of the weed. A follow up treatment should be made in the spring. Forefrot gives the most reliable control of ragwort, or alternatively,  Lupo + Fortune wetter also shows useful activity

Docks are a particular problem in intensively managed grassland, especially where seeds are spread through slurry applications or poaching has occurred. Docks look unsightly, but more importantly, can reduce the grass yield and productivity. Early autumn is often overlooked as a potential time to achieve effective dock control.  At this time the dock plant will revert back to vegetative growth.  During vegetative growth the plant food being produced in the leaf is moved into the root for storage. Translocated herbicides are moved through the plant along with the food, hence if they are applied at this stage more product will end up in the root giving better root control.

Where clover is not considered important sprays based on the chemicals fluroxypyr, triclopyr or dicamba/mecoprop mixtures should be used. If clovers are an important component of the sward Squire Ultra may be used .Remember in most circumstances treatment is most effective where a second application takes place within a 12 month period.

Chickweed is an annual weed and seeds will germinate at any time of year but particularly in autumn when growing without competition from other plants. Common chickweed can produce approximately 800 seeds and it takes 7 to 8 years for the seed bank (supply of viable seeds in soil) to be 95% depleted, insuring an infestation for many years. Because of its ability to produce large numbers of seeds under cool temperatures, common chickweed rapidly colonizes any cool, moist area before winter or spring crops can become competitive.

Potatoes

Growers should continue to maintain fungicide protection of the haulm until the crop is harvested or the haulm is 100% desiccated. Timely desiccation is an essential part of good seed and ware production. Diquat is the most widely used farmer applied chemical desiccant .The rate of haulm desiccation is slow and therefore fungicide protection should continue after application. Even after two split applications of Reglone certain varieties of potatoes are difficult to burn off completely and be certain no regrowth will appear. Spotlight Plus is a desiccant recommended for use after a 7 day interval as a follow up T2 treatment to the T1 application of Reglone and gives complete kill of any stems remaining and stolons below the ground but it is poor on leaves.