Pesticide ban and ‘new’ ways to beat weeds

After farmers using the common pesticide metam sodium had difficulty breathing, it was banned in France until February for tests. Similar fears on other pesticides prompted a national ban on councils using chemicals in parks and, as Brian McCulloch finds, encouraged other ways of working

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Communes have had to find new methods of killing weeds since pesticides and herbicides were banned in public parks and gardens 18 months ago.

That has meant blow-torches, hot water or even councils going back in time and getting their workers to hoe out weeds.

Even before putting the ban in place, the government had been encouraging communes to go “zero-pesticide”.

Since 2015, those doing so can use the label Terre Saine (healthy ground).

So far, 317 communes have won the label, and another 4,200 are aiming for one.

It means not using pesticides, including anti-moss preparations on roads and paths, for at least a year.

One Terre Saine village is Blanzac in Charente, which meets all the criteria and was awarded the highest distinction, a four-butterfly symbol.

Mayor Jean-Philippe Sallée said their solution was simple. “Elbow grease! Our team in the parks and gardens uses gas blow torches at the start of the growing season, then mainly the hoe.

“But what is important, too, is we ask the population to look after the weeds in front of their houses and businesses, and that means the workload on our staff remains reasonable.

“Most do... but some say they pay their taxes for the town to do the work.”

The town’s streets have a slightly shaggier look but the move has had support in spite of the extra cost, with an extra gardener hired.

A sit-on strimmer was also bought, but did not cope well with the medieval streets’ narrow and uneven pavements.

The cemetery is the biggest problem, with residents refusing to accept weeds in the paths and around graves.

“We have put in Japanese-style stepping stones in what used to be gravel paths and it has made things look better, and calmed people down,” Mr Sallée said.

“Using less pesticides is important for all sorts of reasons and we, as elected members, have to take a lead.”

The move against weedkillers has also encouraged the use of new machines in vineyards.

For a long time, vignerons have sprayed weedkiller, usually twice a year, along the foot of each row of vines as yields are higher if there is no grass there.

Now powered hoes, driven from a tractor drive, can clear weeds at the vine base – but vignerons say they are costly to buy and use and damage the vines.

Brittany led France 10 years ago when it banned pesticides in public parks and gardens and that gave inventor Jean-Pierre Barre the push to manufacture an alternative weedkiller, using very hot water.

Called Oeliatec, it is fed by a mobile boiler, fuelled by central heating oil, to heat and pressurise water to 120C.

Using a lance, the operator squirts scalding water on to weeds, killing them quickly. Units cost €16,000-€78,000 and are bulky and heavy, needing batteries and electric motors to lug them around, which involves using a trailer.

So far, 700 have sold, mainly to local councils, and one satisfied customer is Le Rheu garden city, outside Rennes, where the Oeliatec unit has been used daily for three years.

Town general manager Damien Carlo said: “We are very happy with it. It is one method among others and it complements the manual methods, using hoes, which we use.”

Its main drawback is the time it takes to manoeuvre, so it is slower than using a hoe – but more efficient at killing weeds in hard-to-reach corners.

Despite the positive experience, he said the town still needs to use chemical weed-killers on paths which are not asphalted and on its sports fields.

He said: “With the paths, they are not sealed, being chalk and gravel, so finding an alternative is difficult.

“We do not want to have to asphalt over the pavements in order to reduce pesticide use, as the environmental damage will actually be greater if we do so, especially with increased run-off into the rivers.”