Grass strips urged to retain oilseed rape herbicides

Growers are being urged to establish 6m grass buffer strips beside watercourses in fields to be sown with oilseed rape or winter beans this autumn or next.

‘At risk’ herbicides 

Active ingredient

Product examples

carbetamide

Carbetamex, Crawler

clopyralid

Dow Shield, Galera

metazachlor

Butisan S, Novall

propyzamide

Kerb Flo, Flomide

Failure to do so could lead to the use of key weed-killers being severely restricted or even banned, industry specialists fear.

With some widely used herbicides increasingly occurring in watercourses which are above EU-permitted drinking water levels, buffers are seen as vital in helping to protect water quality and permit their future use.

A new free HGCA information sheet* highlights the risk of the UK not meeting the Water Framework Directive’s demands. “To avoid further use restrictions, or even a ban, the industry must change field management practices,” it states.

“Latest evidence from the crop protection industry shows 6m grass buffer strips can reduce pesticide loss through surface run-off by over 50%,” says Voluntary Initiative manager Patrick Goldsworthy.

Many farms have such strips installed under stewardship schemes, but there is scope for plenty more, according to TAG‘s Jim Orson.

DEFRA estimates that 37% of streams are buffered on at least one side and many main rivers have grass margins beside them, he notes. “It’s the feeder streams that are more of an issue.”

NFU combinable crops board chairman Ian Backhouse hopes more farmers will take advantage of ELS to create such pesticide barriers, as many have already done so for LERAP purposes.

“The measures within ELS not only benefit wildlife – they act as a means of resource protection,” he says.

However, the relatively late VI request could cause difficulties for some farmers during a busy period, he adds. “It’s another job to do.”

The temptation could be to leave new margins fallow to be grassed down later. But for maximum effect they must be grassed at least a year before crop sowing, warns Mr Goldsworthy.

“We’ve got to bite the bullet now. Farmers should look to establish buffer strips for both 2009 and 2010 plantings of both oilseed rape and winter field beans.”

Buffers help the Pelletwise campaign to keep metaldehyde out of water he adds.

The minimum width on all soil types is 6m, but in fields steeper than 1in 20 (>5%) 20m is advisable.

One way to ease the burden of their creation might be for farms bordering watercourses to cooperate, with one doing the sowing on behalf of others, he suggests. Alternatively, contractors could be employed.

Natural England’s Ross Evans confirms that farms are allowed one amendment to each ELS scheme. “It is very straightforward and involves minimum paperwork.”

“It is definitely an opportunity for us to help,” says Oxfordshire-based contractor James Gilles of Valeag. “We’re all geared up for doing it and we are used to multiple invoicing.” His equipment includes a 1m wide drill for extending 2m and 4m wide ELS margins.

Dow Agroscience trials in Leicestershire show perennial tussocky grass species are best at reducing run-off, says Alastair Leake of Loddington Estate.


*HGCA Information Sheet No 9/Summer 2009 ‘Oilseed rape herbicides and water protection’ will be posted to all levy payers later this month.