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Pine-tree lappet moth

Summary

This research is being undertaken to determine whether the pine-tree lappet moth (Dendrolimus pini) is an introduced species and meets the criteria of a quarantine pest or is a previously undiscovered resident; also to develop standardised survey protocols, and establish the life-cycle and biology of the species in the UK, to guide future management and control.

About the pine-tree lappet moth

The pine-tree lappet moth (Dendrolimus pini) is native to, and widely distributed within Europe, and its range even extends into parts of Western Asia.

Pine-tree lappet moth caterpillar eating Scots pine needle. Location: Northern Research Station, Roslin, Midlothian, Scotland.
The caterpillars of this moth (above), which grow to 80mm (3 inches) in length, feed on Scots pine and occasionally other tree species and can be major defoliators in some parts of their natural range. They can cause extensive damage and tree death over large areas of forest and this frequently requires aerial insecticide application to control the outbreaks.

Male Pine tree lappet moth. Location: Northern Research Station, Roslin, Midlothian, Scotland Female Pine tree lappet moth. Location: Northern Research Station, Roslin, Midlothian, Scotland
Adult male pine-tree lappet moths (above left) are large with a wingspan of about 60mm (2.5 inches), while females (above right) are even larger at 80mm (3.2 inches).

There have been occasional captures of migrant male moths arriving on the south coast of England but they have never been found breeding there. The first recorded capture of a moth in Scotland occurred in 2004 and they were first shown to be breeding in pinewoods to the west of Inverness, including in Forestry Commission’s Boblainy forest, in 2009.

This research is being undertaken to determine whether the moth is an introduced species and meets the criteria of a quarantine pest or a previously undiscovered resident as well as to develop standardised survey protocols, and to establish the life-cycle and biology of the species in the UK, to guide future management and control.

Research objectives

  • Develop standardised survey techniques to monitor pine-tree lappet moth.
    Tree bands used to survey for pine-tree lappet moth caterpillars Tree bands used to survey for pine-tree lappet moth caterpillars
  • Apply survey methods to monitor the extent and size of the population over time.
  • Assess methods for minimising the risk of transporting life stages out of the outbreak area during tree felling operations.
  • Investigate the phenology of pine-tree lappet moth.
  • Determine growth, consumption, and development rates of the caterpillars and adult fecundity.
  • Determine relationships between caterpillar populations and foliage damage.
  • Use genetic / DNA studies to clarify the origin of the Scottish moth (native or introduced).
  • Use climate modelling to determine the risk of outbreaks now and in the future.
  • Look for predators and parasites of PtLM and the potential of a range of control agents.

Pest risk analysis

European PRA for Pine-tree Lappet Moth (PDF-158K)

Funders and partners

Butterfly Conservation logo Forestry Commission logo
Our partners for the work on D.pini are Butterfly Conservation Scotland and the work was funded by the Forestry Commission (GB), Forestry Commission (Scotland) and Forest Enterprise (Scotland).

SNH logo CONFOR logo
Scottish Natural Heritage are part of the Forestry Commission Outbreak Management Team as are CONFOR.

Forestry Commission policy

The pine-tree lappet moth is not subject to regulation under the European Plant Health Directive – as the pest is endemic in its native range in continental Europe – or listed in the Plant Health (Forestry) Order 2005.

However, due to the potential risk this insect poses to British trees a containment programme has been launched using the general powers under the Order to deal with pests not normally present in Britain.  Research is therefore now being undertaken to determine whether the moth is an introduced species and whether it will meet the criterion of a quarantine pest, either now or in the foreseeable future.

See Forest Commission Plant Health Service for further information on plant health issues.

Status

Research commenced in 2009 and is scheduled to continue until 2014.

Contact

Dr Roger Moore