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I am amazed at the extent of damage in both winter cereal crops and grassland from leatherjackets already this season. Leatherjackets are the larvae of the crane fly or ‘daddy long legs’ and cause widespread damage to cereals, grassland, root crops and vegetables. Eggs are laid in the early autumn, and the larvae hatch and feed over the winter period.

Leatherjacket numbers are much higher this spring than they have been for many years. Where fields are looking poor or yellow, or bare patches have appeared, it is essential to inspect for leatherjackets. Damage is already becoming apparent in some established grass swards. With this evidence of high leatherjacket populations, spring cereals are also certain to be at risk, especially those following a grass ley. As crops are most susceptible to damage at the seedling stage it is most important to monitor leatherjacket numbers from emergence onwards.

In newly sown cereals the need for treatment is assessed by scratching along 30cm (12“) drill lengths to a depth of 5cm and searching for leatherjackets. The following grub numbers are the threshhold figures at which damage is likely to occur: -permanent pasture-100/m2 -spring cereals -50/m2 Young cereals are attacked both below and above the ground. To limit damage leatherjackets need to be detected before they have had a chance to do serious damage to your crops. A good early indicator of high populations is the presence of birds, in particular rooks, crows and starlings, in fields as they search for the grubs. Symptoms of leatherjacket damage are yellow dead plants or withered patches of grass that have been cut off from their roots just below the ground. On closer examination leatherjackets can be found by digging in the top 2-3 cm of the soil. At this time of year they are typically 1-2 cm in length grey in colour with a tough leathery coat, hence their name, and resemble a large maggot.

If numbers meet the threshold, chemical treatment should be applied using a product containing chlorpyrifos such as DURSBAN WG or CYREN. As the leatherjackets live in the soil the spray must reach the soil therefore a high water volume (500l/ha) is essential and a coarse spray quality to ensure good penetration into the soil surface. Light rain after the spray application will also help.

DursbanWG at 1.0kg per hectare gives the highest level of control of leatherjackets as it is strongly absorbed onto the clay particles in soil persisting for up to 6-8 weeks.  Dursban’s unique formulation is based on a novel free-flowing granule containing 75% chlorpyrifos – the most concentrated active ingredient loading of any chlorpyrifos product. It is important to note when using an induction hopper a continuous flow of water through the hopper must be maintained. The sprayer should be half full before adding Dursban to the tank.  When using a filter basket this must be removed and the Dursban WG added to the tank in a steady even flow maintaining agitation.

Chlorpyrifos is judged to be non injurious to birds and, at dose rates likely to result from commercial applications, little or no effect has been detected on overall populations of soil fungi, bacteria or algae.Dursban has also been shown to have little effect on earthworms and other beneficial arthropods.

The drier conditions over the last week have been a welcome sight. Winter cereal crops on the whole have struggled with the persistent wet conditions since drilling. Many crops have also been decimated by slugs over the winter and more recently leatherjacket numbers have rocketed. Hopefully all crops have received their autumn herbicide for the control of broad leaved weeds and annual meadow grass but there is still an opportunity to apply residual herbicides to late drilled crops. Othello is still an option going into the spring for grass weed control where the grass has begun to tiller (on winter wheat only). Most crops are now beginning to seek fertiliser and now is the time to assess which fertiliser is to be applied according to the soil analysis. Cereal pricing still remains strong but this is overshadowed by the rising cost of fertiliser and other essential commodities to grow crops. It is more important than ever to carry out soil samples with soils of index 3 for P&K being the optimum level for agricultural land. I feel there is still not enough emphasis put on the importance of PH levels in the soil. Where ph is low the soil is unable to utilise the nutrients in the fertiliser, ph of 6.5 is ideal to grow cereal crops with 6.0 being more suited to potato crops.Landscapers have been working away through all the wet weather but pruning and other work has been difficult with current ground conditions. Unfortunately with the extreme weather conditions experienced over this winter many trees and shrubs have died and will need replacing.

Winter is the best time to control weeds around young hedges and trees. 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 that provides selective, broad spectrum weed control.

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.

Agrochemicals and fertilisers are major variable inputs in growing crops and the way they are applied has a great influence on their efficacy.

It is essential therefore that the equipment used to apply them is well maintained and accurate.

Sprayers should be calibrated regularly. One of the most important areas of the sprayer is the nozzle. Nozzle output should be measured to check that it is the same as the value in the calibration chart for that type of nozzle. Nozzles with a variation of more than 5% should be changed.

Money spent maintaining the sprayer is money well spent as a properly calibrated sprayer will reduce wastage of agrochemicals and will improve their performance.

Similarly fertiliser sowers should be calibrated and if possible get a tray test carried out to check the spread pattern as striping in crops is often caused by uneven fertilizer application, which again wastes money.

Kerb granules is a pre- or post-emergence residual herbicide that provides long term residual control of annual and perennial grasses and a wide range of other weeds in farm and commercial forestry, ornamental plantings and recreation areas.KERB is commonly used along fence lines and gravel pathways. KERB may be applied to all soil types however efficacy may be reduced on soils with high organic matter. Propyzamide the active in KERB works by inhibiting cell division which disrupts growth and gradually works through the root system leading to eventual death of the target weed.KERB granules are mobile in the soil profile and therefore the best results will be achieved in cooler conditions. 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 runoff.

The present weather conditions are ideal for KERB application. KERB granules can be used on all ornamental trees, shrubs and roses. Where shrub beds are mulched KERB must be applied immediately prior to mulching to prevent weeds from growing through the mulch.KERB takes the worry out of weed control economically. With just one application per season trees, shrubs and borders can be cost effectively protected from invasion and competition by weeds.KERB granules are non-irritant, non sensitising and have no known bio-accumulation potential and are non-ecotoxic which means KERB products are veryr/ safe to use.