Horse-chestnut leaf miner

The horse chestnut leaf miner Cameraria ohridella is a moth of the lepidopteran family Gracillariidae. It probably originated in Asia, and first appeared in Europe in 1985. The moth grows up to 5mm long and has shiny, bright brown forewings with thin black and white stripes. Its larvae feed on the leaves of the Common Horse-chestnut (Aesculus hippocastanum), causing significant damage to the trees.

The larvae digs its way into the leaves of the tree, damaging the leaves and stunting growth. Infected leaves are covered in small brown patches which spread rapidly across the entire tree, giving an autumnal appearance (these patches are similar to damage caused by the fungus Guignardia aesculi , but can be distinguished by their more regular size and shape). Eventually the leaves die and drop off; when new ones grow they are again infected. This cycle can repeat itself several times in one season.

Cameraria ohridella has now been found in Ukraine, England, Belgium, Croatia, the Czech Republic, France, Germany, Hungary, Italy, the Netherlands, Poland, Serbia, Slovenia, and Switzerland.

The moth is able to live at temperatures as low as -23°C, although it thrives in warmer climates, where it can achieve as many as six generations a year. Its natural enemies are parasitic wasps, but there are few of the required species in Europe, meaning there is next to no natural control.

Since 2001 an EU-wide multidisciplinary project, CONTROCAM ("Control of Cameraria"), has been trying to predict how much of an impact Cameraria ohridella will have, and to find methods of pest control.

Spread of Cameraria ohridella across Europe

• 1985 Macedonia
• 1989 Austria
• 1996 Germany
• 1997 Hungary
• 1998 Czech Republic
• 1999 France
• 2002 England
• 2003 Ukraine

External Links

• Cameraria Homepage in German and English
• Prague University Cameraria homepage in English