Leaf Hoppers
Cicadellidae
Leafhoppers are sap-sucking insects that cause stippled, bleached foliage and can spread plant pathogens in nursery and horticultural crops.
Leafhoppers are small, wedge-shaped insects belonging to the family Cicadellidae, a large and diverse group with many species affecting ornamentals, vegetables, turf and broadacre crops across Australia. Adults are typically 3-10mm long, slender and tapered towards the rear, with colouring that varies widely between species from pale green or yellow through to brown, mottled or brightly patterned. They hold their wings roof-like over the body and are strong jumpers, often flying or hopping rapidly when disturbed. Nymphs resemble wingless miniature versions of the adults, pale green to translucent, and move sideways in a characteristic scuttling motion when approached. Both adults and nymphs are usually found on the underside of leaves or along stems, where they feed with piercing-sucking mouthparts.
Leafhoppers feed by inserting their mouthparts into leaf tissue and withdrawing plant sap, and some species also feed on or lay eggs within stem and leaf tissue, causing mechanical damage independent of the feeding itself. Certain species are also known vectors of plant pathogens, including phytoplasmas and viruses, making them a concern beyond direct feeding injury in some crops.
These insects are present throughout Australia and can be active for most of the year in warmer regions, with populations typically building through spring and summer as temperatures rise and host plants put on new growth. Many species have multiple, overlapping generations per year, and populations can increase rapidly under warm, dry conditions.
Management in professional horticulture and nursery production relies on regular crop monitoring, particularly checking leaf undersides for nymphs, and maintaining good crop hygiene by removing weedy hosts around production areas. Yellow sticky traps are useful for monitoring adult flight activity, and encouraging beneficial predators such as lacewings, ladybirds and predatory bugs can assist in suppressing populations in less intensive production settings.
How to identify
- Stippling or bleaching: Fine, pale or silvery speckling on leaf surfaces where cells have been emptied by feeding, sometimes progressing to a bronzed or scorched appearance under heavy infestation.
- Distorted or stunted growth: New shoots and leaves may curl, pucker or fail to expand properly, particularly where nymphs feed on developing tissue.
- Honeydew and sooty mould: Some species excrete honeydew, leading to sticky leaf surfaces and secondary sooty mould growth.
- Shed skins: Small, pale, cast nymphal skins may be visible on the underside of leaves after moulting.
- Field check: Tap or gently shake affected foliage over a sheet of white paper or your hand — leafhoppers will jump or fly off readily, distinguishing them from slower-moving pests. Turning leaves over will often reveal nymphs sheltering on the underside.
- Lookalikes: Leafhoppers can be confused with planthoppers, which are generally broader-bodied and less active jumpers, and with aphids, which are soft-bodied, slow-moving and do not jump or fly readily when disturbed. Psyllids are another lookalike but are typically smaller and more uniformly cicada-shaped at rest.
