Giving Up On Pesticides

In a recent biodiversity study carried out in nine regions across Europe, agricultural scientists from Göttingen University analysed the effects of 50 years of increasingly intensive farming on plants, beetles and birds.

The result was that doubling a field’s cereal production would halve the number of plant species – and the species of birds and beetles would drop by a third.

The main reason is the increasing use of pesticides such as insecticides and fungicides. The report concluded that organic farming can’t do much to halt the loss of species so long as the majority of farmers continue using pesticides.

Organic farming is kind on plants and beetles, but birds, butterflies, bees and other mammals are all dependent on wide living spaces.

“If you want biodiversity, you need to forgo the use of pesticides to the greatest possible extent,” Teja Tscharntke, leader of the study, told swissinfo.ch.

Tscharntke, professor of agroecology at Göttingen University in Germany, added that the study results could certainly be applied to Switzerland.

Value of pesticides

“It is our goal that the use of pesticides is kept to a minimum in Switzerland,” said Samuel Vogel, head of ecology at the Federal Agriculture Office.

“Swiss agricultural policy contains various clauses that should guarantee this. On the one hand pesticides are thoroughly tested, and on the other, every farmer has to produce an ecological performance certificate to get financial assistance.”

Farmers can then only use pesticides if the amount of weeds exceeds the damage threshold, in other words, results in crop losses.

He added that a total renunciation of pesticides would result in yields dropping dramatically.

“In the 18th century, part of the emigration from Ireland was down to potato blight. There was nothing anyone could do about that fungal disease, which can destroy a farmer’s yield completely,” he said.

Weeds can also lead to a drop in yield of up to 50 per cent. Not using pesticides on cereals for example brings in ten per cent less yield, according to Vogel.

Work to be done

But biodiversity also has a high status in Switzerland, which has for example signed the biodiversity convention, anchored ecological compensation areas in law and supported organic farming.

“There is a range of measures supporting biodiversity not only in agriculture but also in forests and nature reserves. The aim is to achieve a general overview,” Vogel said.

According to Swiss law, at least seven per cent of every farmer’s land must be an ecological compensation area.

“That is unique to Switzerland – nowhere else in Europe has that,” he said, pointing out that these areas, for example hedgerows or fallow land, are good for beneficial organisms as well as plants.

The size of these increased steadily until 2002, since when it has stagnated at around 120,000 hectares. The majority of this is meadow (70 per cent) and fruit orchards (20 per cent).

But despite these efforts the biodiversity balance on the Swiss lowlands is relatively poor – although Vogel says Switzerland is not alone with this problem.

“The high population density definitely has a big influence. A large part of the countryside is already overbuilt and will continue to be so. Here there is a great need for action,” he said.