PEST
 
   NAME
     Sawfly (General)
     Various Sawfly Species
 
   ORDER
     Hymenoptera

Description of the Pest
Adult sawflies are wasps that have derived the name Sawfly from the sawing action to open leaves using there ovipositor. The adults are usually colourful insects. The fleshy larvae normally are tapering caterpillars, some with pointed spine on the tale and are many different colours from black-blue to brown and orange.
These insects have a Holometabolous life cycle, ie. When metamorphosis is observed during the pupal stage.

They are commonly called “spitfires” because, when disturbed, they bend back their bodies and exude a strong, eucalyptus-scented liquid from their mouths. This exudate contains concentrated eucalyptus oil, which can cause severe eye irritation. The non-feeding adults are seldom seen. Sawflies have a complete metamorphosis, pupating in cocoons in the soil for months or years.

Eucalyptus Sawfly (Perga kirbyi) lava is pale brown up to 40mm long. It is a plump grub with a black head and a yellow tipped tail and can be found in groups during the day, but spreads out at night to feed. When disturbed they react by arching there head and wiggling there tail. 

European Spruce Sawfly (Diprion hercyniae) feeds on the old growth causing stunting of the host and the larvae overwinter in cocoons on the ground.

Ironbark Sawfly (Lophyrotoma interrupta) is a fleshy tapering grub up to 40mm long. It is pale brown with a black head and a yellow tip on its tail. 

Long-tailed Sawfly (Pterygophorus insignis) larvae are greenish with a textured surface and a long pointed tail. 

Pin Oak Sawfly (Caliroa lineata) adult is shiny-black up to 6mm long with four wings and the greenish larvae is up to 14mm long. It feeds by skeletonizing the underside of leaves turning them golden-brown as they die and an infestation in a large Quercus species is easily recognisable.

Pine Sawfly (Zenarge turneri) lays larvae that are rough and fleshy up to 10mm long with the abdomen curled.

  Steelblue Sawfly

The adult Steelblue Sawfly (Perga dorsalis) female is steel blue in colour, with yellow antennae and legs, growing up to 20mm long, with 40mm wingspans. The insect is called a “sawfly” because of the sawing action of the ovipositor. The yellowish-brown larvae have chewing mouth parts. 

Appearance of the Pest
During the day, sawflies congregate in clusters, separating at night to travel and feed on the foliage of the host plant.

Period of Activity
Caterpillars appear in spring through summer and are found from tropical to sub-tropical and temperate regions.

Susceptible Plants
There are many ornamental and Australian native plants that are attacked including Eucalyptus camaldulensis, E. blakelyi, E. melliodora, and E. pauciflora and Callistemon, Leptospermum species. 

Eucalyptus species are attacked by the Eucalyptus Sawfly (Perga kirbyi) which can defoliate a tree.

Larix species are attacked by the Larch Sawfly (Pristiphora erichsonii). The adult wasp-like fly deposits eggs in an incision on the twigs during late spring and the 25mm long olive green spiny larvae chew the needles. The larvae overwinter on the ground in brown cocoons.

Melaleucas are also attracts the Paperback Sawfly. 

Pinus and Callitris species are attacked by up to four species including the Pine Sawfly (Diprion simile).

Sorbus aucuparia is attacked by the Mountain Ash Sawfly (Pristiphora jeniculeta). The larvae feed on the leaves, leaving only the mid rib and main veins.  Heavy infestations causes serious defoliating of the tree.

Viola species are attacked by the Sawfly (Ametastegia pallipes)  which eats the leaves skeletonising them. 

Damage Caused
Generally the larva eat the surface of leaves, skeletonising them when young, but as they develop they eat large pieces leaving only the mid rib. They tend to feed on the terminal shoots, and heavy infestations can defoliating young trees.

Cultural Control
Clustering larvae may be hosed or knocked from branches, falling to the ground where they can be squashed under foot or attacked by other predators. At night when the larvae congregate they can be collected and disposed off. In small infestations they can be picked by hand and destroyed. 

Biological Control
The exudate causes most birds to avoid the larva, although cockatoos remove the head and oil gland prior to consumption. They are also eaten by lizards and frogs or attacked by parasitic wasps.

Chemical Control
Affected plants can be sprayed using Maldison or Carbaryl, this is only possible for small trees.
Note
Always read the label for registration details and direction of use prior to application of any chemicals.