PEST

NAME
Case Moths, Bag moths
Various Case Moth
Species
ORDER
Lepidoptera

FAMILY
Psychidae

Description of the Pest
Also called the bag moth or bagworm - so called because of the silken, bag or case-like structure in which they shelter and pupate.       The pendant case is frequently covered with twigs, pine needles, sand or leaf fragments, which serve to reinforce and camouflage it. The case is enlarged as the caterpillar grows and the upper part of the body emerges for feeding and movement. It withdraws into the case if threatened or disturbed.

     
Case moth feeding           The head protrudes from the case to feed

Leaf Case Moth(Hyalarcta huebneri) constructs a short cocoon that has a ragged appearance and is covered in leaf and bark pieces. The caterpillar is orange with black bands and can grow to 50mm (2in) long. This pest can be found on Eucalyptusand Leptospermumspecies, it may also attack palms from sub tropical to tropical regions.

Ribbed Case Moth(Hyalarcta nigrescensi) forms a greyish cocoon that has four prominent ribs and taper at the base. It feeds solitary on AcaciaandEucalyptusspecies by chewing on the leaves or removing the epidermal layer of the leaf.

Saunders Case Moth (Metura elongatus) forms an elongated silken bag composed of small pieces of twig and is up to 150mm (6in) long. The caterpillar is dark red with yellowish bands and markings. It is commonly seen from temperate to tropical regions feeding on leaves of Eucalyptus, CallistemonandEpacrisspecies. When disturbed it hides in its cocoon and control is not normally required.

Saunders Case Moth Ribbed Case Moth Leaf Case Moth

Well Camouflaged

Life Cycle
This insect has a Holometabolouslife cycle, i.e. it has alarvaland a pupal stage.
The larval stage can last up to 2 years.
The male moths can fly. In some species the females are wingless, or have greatly reduced wings.
In some species the females can lay over 10,000 eggs.
Larvae pupate in their cases. Newly hatched larvae disperse and construct their own cases.

Distribution of the Pest
They are widespread across most temperate to tropical Australia.

Damage Caused
Larvae eat leaves and on masse they may cause considerable damage.
Larvae and their cases are difficult to detect among foliage.

Period of Activity
Larvae are more numerous and active during the warmer months.

Susceptible Plants
A wide range of plants are susceptible to case moth larvae, with different moth species favouring different plants. Host plants include eucalypts, acacias, pines and conifers.

Callitrisspecies are attacked by the Stick Case Moth(Clania ignobilis) that constructs a cylindrical cocoon of aligned twigs with a projecting twig at the base and feeds on small or young foliage. It is not a major pest causing little harm.

Larixspeciesare attacked by the Larch Casebearer(Coleophora laricella). The caterpillar forms a cigar-shaped case from pieces of needles. It feeds on the needles in late spring by forming a hole either end or the middle of the leaves and mining the centre with out leaving its case. It then overwinters in its case attached to the twigs and the moth emerges in early summer.

Control

Cultural Control
Early detection and control of infestation is important with some species; they may be removed by hand.

Biological Control
Birds are natural predators.

Chemical Controlis possible, but this is not usually necessary.

Note
It is your responsibility by law to read & follow the directions on the label of any pesticide

Amendments by B. Sonsie Dip Hort Sc Burnley