Leafroller caterpillars
Leafroller caterpillar with silken threads used to hold the leaf together (leaf unrolled for the photo)
© NSW DPI
Leafroller caterpillar adult (Strepsicrates sphenophora)
© Donald Hobern
Leafroller caterpillar inside rolled leaves
© NSW DPI
Leafroller caterpillar damage; note the curled leaves and defoliation
© NSW DPI
Leafroller caterpillars feed on young leaves, commonly in growing shoots. Some caterpillars web leaves together as a shelter, while others roll a leaf over and use silk to hold it in place.
These caterpillars rarely cause significant damage, but they can affect the form of newly planted trees, especially in nurseries and young plantations.
Scientific name
Strepsicrates species
Description
- Caterpillars:
- are 10–20mm long and around 3mm wide
- have various colours (grey-green, light green, pinky red or light brown)
- have shiny heads, often of a different colour to the body (black, light green or light brown).
- Moths:
- are greyish or brownish and inconspicuous
- are of medium size
- have a wingspan of 10–20mm and narrow wings.
Distribution
- Throughout Australia from temperate to subtropical regions and from coastal to inland areas
Hosts
- Many Leptospermum and Eucalyptus species
- Dunn's white gum (E. dunnii)
- Rose gum (E. grandis)
- Tallowwood (E. microcorys)
- Blackbutt (E. pilularis)
- Swamp mahogany (E. robusta)
- Sydney blue gum (E. saligna)
- Forest red gum (E. tereticornis)
Damage
- Leafroller caterpillars feed on young leaves and use them to create shelters.
- Young caterpillars tend to scour the leaf surface. Mature caterpillars skeletonise or feed on the edges of leaves.
- These caterpillars rarely cause significant damage. However, they can affect the form of newly planted trees, especially in nurseries and young plantations.
Biology
- Eggs are usually deposited singly on the host plant, rarely in small irregular clusters.
- Larvae feed on leaves by night and shelter in rolled leaves held together by silk during the day.
- Pupation also takes place in these shelters.
- Moths are mostly active early in the evening and at night.
- Most species have several generations per year, especially in the moist tropics and subtropics.
Control
- These caterpillars do not usually require control.
- When clustered together, caterpillars can be squashed or dropped into boiling water.
Resources and research
- Carnegie, AJ, Lawson, SA, Smith, TE, Pegg, GS, Stone, C, McDonald, JM, 2008, Healthy hardwoods: a field guide to pests, diseases and nutritional disorders in subtropical hardwoods, Forest & Wood Products Australia, Victoria.
- Horak, M, Komai, F, 2006, Olethreutine moths of Australia (Lepidoptera, Tortricidae), CSIRO, Collingwood, Victoria.
- Jones, DL, Elliot, WR, Jones, SR, 2015, Pests, diseases, ailments and allies of Australian plants, Reed New Holland Publishers Pty Ltd, Chatswood, NSW.