Rentokil Declares War on Oak Processionary Moths

29 July, 2005

Motorists on the A73 autobahn between Bamberg and Nuremberg (Bavaria) might catch a glimpse of a strange sight over the next few weeks – workers in full-body protective garb hoovering trees. Vacuuming the woods might seem odd, but it is the best way to get at the larvae of the Oak Processionary Moth. These moths go through an exceptionally obnoxious adolescence. Not only do the voracious caterpillars kill oak trees, they also endanger people, with toxic hairs that can cause itching, rashes and even asthma on contact. As the caterpillars cross the ground moving from tree to tree, they endanger children and domestic animals. Attempts to combat them with water cannons, insecticide and even gas burners have not been successful.

Environment-friendly pest removal

The motorway authority in Bayreuth is using a technique developed by the technology department of Rentokil Initial GmbH to protect motorway workers from the poisonous caterpillars and put a stop to rising sickness rates. The process uses a mix of special plant oils to bind the allergenic hairs, which can then be vacuumed off. During the coming weeks, a total of 800 trees along 200 kilometres of motorway will be treated.

“We’ve been looking for an efficient, environment-friendly and cost-effective way to slow the spread of this problem,” explained Jürgen Althoff, Technical Director of Rentokil. The advantage over fire or pesticides is that vacuuming prevents the toxic hairs from spreading, and of course there is no fire hazard. To protect themselves from the toxins, Rainer Mackenrodt, director of the Rentokil office in Nuremberg, and his staff cover themselves head to toe in hazmat suits with breathing masks. “It’s a real bother, especially in summer, but it keeps us safe,” said Mackenrodt. And the job doesn’t end when the oaks are free of pests. Service technicians Ibrahim Kicin and his colleagues hoover out up to 70 kilos of insect tissue per tree. At 800 trees, that’s a lot to handle.

During the course of the campaign, 10 trucks will haul away 56 tonnes of defunct pest to a special disposal site. Since the long, dry summer of 2003, the caterpillars of the Oak Processionary Moth have become a plague in southern Germany, making drastic measures necessary to protect people in general, and motorists on the A73 in particular. The wind can blow caterpillar hairs 200 metres through the air, and the toxins can cause rashes and asthma up to a year after the caterpillar has turned into a moth and flown away.