Destructive new pest removed from RHS Garden Wisley

Oak processionary moth discovered at the flagship RHS garden; control measures have been taken

Oak processionary moth (OPM) has recently been discovered by staff at RHS Garden Wisley. RHS staff had been monitoring the garden for this insect, following reported sightings in June less than 10km (6mi) from the site. The nests have been professionally removed and all oaks in the garden have been inspected.

Oak processionary moth (Thaumetopoea processionea, often abbreviated to OPM) is native to southern Europe but is now pervasive on the Continent. It was accidentally introduced to Richmond upon Thames with imported oaks in 2005.

Although control measures have been taken, it has become widespread in west London and there have been outbreaks in Berkshire, Bromley and Croydon. The Forestry Commission is working with partners to minimise the moths’ spread and impact.

Matthew Pottage, Deputy Curator at RHS Garden Wisley, says: “An OPM management programme is in effect at Wisley and all of our trees are routinely monitored for signs of the caterpillars and their nests. In August 2015, we found our first instance of OPM on site, however we were fully prepared, with measures and expert horticultural and scientific teams in place to tackle the problem swiftly to minimise its impact.”

RHS Garden Wisley is also working closely with the UK Forestry Commission to ensure the garden remains a safe and beautiful place for staff and visitors.

RHS Garden Wisley remains open and fully accessible.

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