Crop protection product manufacturers Adama and BASF are collaborating over a Europe-wide stewardship campaign to safeguard the future use of the oilseed rape active ingredient metazachlor. The initiative follows concern from water companies over levels of herbicide actives in drinking water, such as metazachlor (MTZ), carbetamide, propyzamide and quinmerac (QMC).
Branded as Metazachlor Matters, the campaign aims to capture the attention of agronomists and their grower clients in order to raise awareness and to act as a ‘call to action’ this autumn.
The presence of pesticides in raw water threatens the UK’s chances of complying with the EU Water Framework Directive (WFD) in place to protect all surface and ground waters. “If the water companies cannot show progress in reducing pesticide concentrations in raw water, there will be further restrictions on their use,” warns Dinah Hillier, catchment control manager at Thames Water. “Water companies need the help of the farming community. We really don’t want these restrictions to happen, because farmers need these products; but farmers must start Thinking Water.”
Dr Jodie Rettino, catchment manager at Severn Trent Water adds: “Metaldehyde is the primary problem, but concerns are growing about the autumn-applied oilseed rape herbicides. We have no effective treatment processes for metaldehyde and we struggle to remove quinmerac. Most other pesticides can effectively be removed when they are at low concentrations, but at a cost. However, when we have a number of pesticides at high concentrations over the autumn and winter, they challenge our treatment processes.”
DEFRA and the Drinking Water Inspectorate (DWI) have supported a voluntary approach to WFD compliance, considering a regulatory approach a last resort in the face of the agronomic challenges facing UK growers. But evidence is needed of a reduction in peak levels of pesticides in water to avoid the risk of further product restrictions. MTZ and QMC could be vulnerable as they have EU product renewals approaching in 2019 and 2020 – hence the need for action now.
In response and as part of a wider European Metazachlor Stewardship Initiative, BASF and Adama have strengthened their autumn guidance for metazachlor use, focussing on agronomic best practice and changing on-farm practices to maintain the long term availability of metazachlor.
The guidance for autumn applications of metazachlor announced today is as follows: Early establishment is key; the maximum dose of metazachlor should be 750g/ha; reducing the amount of active ingredient applied reduces the risk of movement to water. Timings: where there are no field drains, there are no application timing restrictions; fields with drainage, including temporary drains, should ideally be treated by 1st October, with a cut off of 15th October; applications after the 1st October can be made as long as soil and seedbed conditions are good and drains are not flowing; drained fields within Drinking Water Safeguard Zones should observe a 1st October cut-off.
“Oilseed rape is an important break crop in the arable rotation. It is especially important on heavy land where spring crop establishment can be difficult. The crop provides an opportunity to manage problem grass-weeds as part of an integrated approach using herbicides with different modes of action to those generally applied in cereals, and provides a good agronomic entry point for wheat in the rotation,” advises Dr Paul Fogg, senior crop team leader at Adama.
“We are reiterating the importance of following the advice issued by the Voluntary Initiative,” adds Rob Gladwin, head of business development and sustainability at BASF. “Growers should aim to establish the crop early, ideally by the first week of September. Also, they should apply metazachlor early, particularly on drained soils where the risk of movement increases the later they are sprayed, and limit metazachlor applications to 750g of active substance per hectare.”