Farming News - Makhteshim brings back chlorotoluron under Water Aware umbrella
News
Makhteshim brings back chlorotoluron under Water Aware umbrella
A key herbicide that cereal growers believed was lost for good is making a comeback in a new product offering early control of meadowgrass and problem broad-leaved weeds.
As part of Makhteshim-Agan’s (MAUK) commitment to position and market products responsibly, Tower will be supported by the company’s Water Aware initiative.
Chlorotoluron had been used until recently, either alone or with diflufenican, at rates of up to 3500g/ha to control meadowgrass, broad-leaved weeds and other grass weeds in cereal crops.
It was withdrawn from sale as a straight in 2010 and three years later as a co-form, due to a lack of data to support lower application rates that would pass the aquatic risk assessment, part of the regulatory process.
Following extensive research and investment by the company, revised rates and timings have enabled the active to be resurrected in Tower, a new product that contains 250g/litre of chlorotoluron plus 300g/litre of pendimethalin and 40g/litre of diflufenican.
At the recommended rate of 2 litres/ha, Tower delivers 500g/ha of chlorotoluron which, with the partner actives, provides excellent control of meadowgrass and a range of broad-leaved weeds when used early in the season, says Paul Fogg, senior crop team lead at MAUK.
“Tower offers a simple, standalone solution to growers across 60% of UK cereal area for which meadowgrass, rather than black-grass, is the main grassweed target.
“It’s proven residual activity also controls key broad-leaved weeds, notably poppy, chickweed and mayweed affected by increasing resistance to ALS chemistry. Other weeds controlled include shepherd’s purse, red dead nettle, speedwell, pansies and cleavers,” he adds.
Tower can be used on winter wheat, winter barley, winter rye and winter triticale. For this first season of use, it can be used early post-emergence at growth stage 10-13. The product may not be used after the end of October and also carries an aquatic buffer restriction of 9m, although this is reduced to 1m at the top of a ditch that is dry at the time of application.
“A revised assessment will be submitted using Drift Reduction Technology – 3-star LERAP nozzles to mitigate the aquatic buffer,” says Dr Fogg. “Further label developments will be introduced to make the product as flexible as possible for farmers.
“We are acutely aware of the legacy issues surrounding chlorotoluron and surface water. Our development plan for the active substance included a critical review of the agronomic drivers and environmental legislation, in particular an assessment on the impact of the Water Framework Directive.
“As part of the new Tower label we have brought application timings forward and away from the high-risk period that coincides with heavy late autumn and winter rainfall. The earlier timing also means we are tackling meadowgrass pre-tillering when plants are small.”
Although there are currently variety restrictions, trials so far indicate no adverse effects on winter barley pre-or post-emergence, and no significant effects pre-emergence on wheat. Further work is needed to assess performance post-emergence on lighter soils, says Dr Fogg.
“The same product is marketed in Germany where it has been possible to remove variety restrictions. We are hoping that we will be able to get to a similar position in the UK.”
Tower illustrates MAUK’s aim to preserve actives responsibly by taking a comprehensive view of the market and analyse the commercial, agronomic and regulatory pressures to see how they might fit in with modern agronomic needs, says Dr Fogg.
“We can ill-afford to lose any more actives,” he adds. “With Tower, we have ended up achieving the same result as older formulations of chlorotoluron in terms of meadowgrass control by doing something a bit different.
“This has satisfied the regulatory authorities and helped to fulfil our aim of keeping proven solutions available for farmers.”