Live "tissue feeding" horse chestnut leaf miner cterpillars sharing a mine. DAVID C. LEE
In 2009, Natural History Museum, London, lepidopterist David Lees joined a project to study horse chestnut leaf miner moths (Cameraria ohridella), which are currently infesting trees across much of Europe, defacing their leaves with distinctive brown scars. Researchers first discovered the insects in 1984 infesting trees in Macedonia, but they weren’t sure where the insects had come from or what might be done to stop them. Entomologists started tracking the leaf miner’s spread in 1989, when the moths suddenly began racing across Europe at the breakneck speed of 60 kilometers per year, finally turning up in Britain in 2002. “Now it’s everywhere,” Lees says.
The insect’s host, the horse chestnut tree, is prized by landscapers for its beauty and in the Balkans its fruits were ...
