The Current Situation with Phytophthora ramorum in England and Wales

David Slawson, Charles Lane, Lynne Bennett & Nicola Parry; Plant Health and Seeds Inspectorate Department for Environment, Food and Rural Affairs (Defra), Foss House, York, YO1 7PX, UK; +44 1904 455169; david.slawson@defra.gsi.gov.uk

Phytophthora ramorum was first found in the UK in April 2002 and emergency EC legislation introduced in November 2002. Since then, official surveys have been conducted and eradication and containment action has been taken against all findings of P. ramorum. The current situation with inspections and surveys is described and data are presented on the impact of the current measures.

The pathogen has been found on various ornamental plants and trees in nurseries and retail premises, and in managed (e.g. parks and gardens) and unmanaged land. The non-tree plant species found to be infected in England and Wales include: Camellia spp., Hamamelis spp. Kalmia latifolia, Laurus nobilis, Leucothoe fontanesiana, Pieris spp., Rhododendron spp., Syringa vulgaris, Taxus baccata and Viburnum spp. Mature trees found infected to date include: Aesculus hippocastanum, Castanea sativa, Drimys winterii, Fagus sylvatica, Nothofagus sp., Quercus cerris, Quercus ilex and Quercus falcata. The disease types found on these hosts are reported.

The total number of outbreaks to the end of September 2004 was 381, of which 123 are ongoing. Of these, 321 outbreaks were on nursery and retail premises, and 60 were in managed and unmanaged land. When comparing the year 2004 with a comparable period in 2003, the number of inspections by the Plant Health and Seeds Inspectorate increased by 56% whilst the number of new outbreaks decreased by 39%. For inspections of material moving in commercial trade there was a 32% reduction in the percentage of positive inspections. For material requiring an EC plant passport, there was a 54% reduction in the number of non-passported consignments and a 94% reduction in positive findings on passported material.

Of the 60 outbreaks on managed and unmanaged land, 9 were found in 2002, 31 in 2003 and 20 in 2004 to end of September. In total, 11 outbreaks have been eradicated and 49 are on-going. Measures required at infected sites are reported.

In conclusion, the import and plant passporting controls appear to have reduced substantially the amount of P.ramorum-infected infected material moving in commercial trade. In contrast, eradication of findings on plants in managed and unmanaged land appears to be a more protracted process.

Back to Schedule