Postcard from... Bonn

Chainsaws and sniffer dogs are the most effective weapons in a vicious war currently being fought in a leafy suburb of Bonn, the city on the river Rhine once famous for being West Germany's political capital.

An army of local authority workers has been hard at work chopping down scores of the city's resplendent maple trees and taking the felled wood to a giant municipal incinerator where it is burned immediately. Over 150 trees have been chopped down so far and many more are certain to follow.

The draconian measures are an attempt to stem an invasion of Asian long-horned beetles – a tree-destroying species considered one of the most voracious in the world. The beetles, which originate in the Far East, eat up trees from the inside. Any tree discovered with their larvae nestling in its bark is considered as good as dead.

In Bonn, special sniffer dogs have even been trained to locate infected trees. The city's environmental experts say wiping out the invaders is the only way to get a grip on the problem.

As a result, hundreds of healthy maple trees are being felled in an attempt to stop the invasion spreading. But many residents are nonplussed. "It's not easy to explain to people that we have to chop down healthy trees to protect the trees," Reiner Schrage, the area's chief forestry inspector, says.

The beetles are thought to have come from a nearby factory that has been importing goods from China since 2005. Central Bonn is renowned for its tree-lined avenues and Mr Schrage warns of a " dramatic outcome" if beetles manage to advance that far into the city.