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Avadex® plays important role for weed management in spring crops

Spring cropping is an effective tool for reducing the populations of grassweeds such as black-grass or Italian ryegrass, which will predominantly germinate in the autumn, so moving the drilling date gives a wide opportunity to remove any seedlings prior to drilling, by chemical or non-chemical means. However, there are some weeds where this technique will not be as successful, with wild oats being a prime example of one. The common wild oat (Avena fatua) is primarily spring germinating, so is likely to be germinating into crops in the next few months. 

Control Options 

If they are emerging in established crops, the only chemical option is to use post-emergence herbicides with ACCase or ALS-inhibition modes of action, to which resistance has already been widely characterised in the UK. In such circumstances, considering inter-row hoeing or harrowing could be a sensible route to follow, particularly if the problem is contained in a small number of fields. For spring sown cereals, there are slightly more options available, with the pre-emergence application becoming increasingly favoured. Where wild oats are the key target, products containing tri-allate such as Avadex® Excel 15G and Avadex® Factor are one of the best options for achieving high efficacy. When used with a partner, almost total control is possible, with any survivors having a fitness penalty because of tri-allate's secondary activity, and therefore being more susceptible to following applications. 

Flexibility is key in the spring 

Spring can be a hectic period, with rapidly changing weather conditions, so developing a management strategy that allows greater flexibility should not be underestimated. Increasing reliance on pre-emergence herbicides means that a significant part of your weed control has been achieved with only particular problem areas requiring additional treatments. For spring barley, there is the added option of applying Avadex® prior to drilling the crop and then drilling through the applied layer. In season’s where seedbeds are drying out, this can help to maintain the level of efficacy from Avadex®  

Early removal key for production 

Whilst weeds, in particular wild oats, can make fields look messy, the real trouble that they cause is the competition for nutrients, water, and light with the crop, reducing yield. Using post-emergence herbicides requires a judgement to be made, often with a compromise to be made. Early applications, against small weeds, are likely to be more effective, however not all weeds will have germinated, so a second application may be needed. Alternatively, relying on a late application may target larger weeds leading to poor control, and the weed has already been competing with the crop. Pre-emergence herbicides such as Avadex® can provide a longer period of protection, coping with extended germination periods, and removing weeds as they germinate and emerge, so prevent competition. 

Other crops 

Using spring cropping is an opportunity to bring additional diversity in the species in the rotation. For weed management this has a multitude of benefits including the use of much later sowing windows, and subsequently later harvest periods. Spring linseed is a familiar crop, producing a blue flower which helps to support on-farm beneficials, whilst canary seed and AhiFlower are two other options also available. Weed burdens are often low in these crops owing to drilling not taking place until April, however when weeds do emerge, they can cause problems when harvesting, but herbicide options are minimal. Avadex® has EAMU approval for use in all these crops, bringing a strong and reliable option against grassweeds and a good range of broad-leaved weeds. 

This spring, think tri-allate, think Avadex®.