Eucalyptus sucker

Eucalyptus is often affected by eucalyptus sucker. Although unsightly the damage caused is not usually serious and can be tolerated.

Eucalyptus sucker ( Ctenarytaina eucalypti ) on eucalyptus

Eucalyptus sucker (Ctenarytaina eucalypti) on eucalyptus

Quick facts

Common name: Eucalyptus sucker
Scientific name: Ctenarytaina eucalypti
Plants affected: Eucalyptus
Main symptoms: Insects on the shoots and sticky honeydew
Most active: Spring and summer

What is eucalyptus sucker?

There are several species of sucker or psyllid that can be encountered by gardeners, they are sap sucking true bugs. Eucalyptus sucker feeds on eucalyptus it is similar in appearance to aphids and up to 2mm long, with grey and orange-yellow nymphs and darker adults. Both adults and nymphs can be found clustered on the shoot tips during the summer.

This Australian insect became established in Britain during the 1920s and is now of widespread occurrence in the UK on Eucalyptus species.  

Symptoms

Shoots where eucalyptus sucker is feeding are often sticky with honeydew and contaminated with sooty moulds. This insect overwinters as adult insects, they lay eggs on shoot tips from February onwards. There are two or three generations a year. 

Control

The damage this insect causes is usually only minor and treatment is not usually necessary. This is fortunate as large trees cannot be effectively treated.

Pesticide control

  • Only small trees can be sprayed, large trees cannot be treated effectively
  • Pesticide sprays are likely to be most effective when the first generation of newly-hatched nymphs first appear on new growth in spring
  • There is no point in spraying later in the year once the feeding damage has occurred
  • Organic sprays, such as natural pyrethrum (e.g. Bug Clear Gun for Fruit & Veg, Ecofective Bug Killer), fatty acids (e.g. Solabiol Bug Free, Doff Greenfly & Blackfly Killer) or plant oils (e.g. Vitax Organic Pest & Disease Control, Bug Clear for Fruit and Veg) can give good control of sucker nymphs. These pesticides have a very short persistence and so may require reapplication to keep suckers in check. Plant oil and fatty acid products are less likely to affect larger insects such as ladybird adults
  • More persistent insecticides include the synthetic pyrethroids lambda-cyhalothrin (e.g. Westland Resolva Pest Killer), deltamethrin (e.g. Provanto Ultimate Fruit & Vegetable Bug Killer) and cypermethrin (e.g. Py Bug Killer)
  • The systemic neonicotinoid insecticide acetamiprid (e.g. Bug Clear Ultra) is also available
  • Follow label instructions when using pesticides
  • Do not spray near plants in flower due to the danger to pollinating insects
  • Inclusion of a pesticide product does not indicate a recommendation or endorsement by the RHS. It is a list of products currently available to the home gardener

Downloads

Pesticides for gardeners  (Adobe Acrobat pdf document outlining pesticides available to gardeners)


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