---
title: Psyllids
canonical: https://fernland.com.au/problem-solver/psyllids/
dateModified: 2026-08-07 09:47:06
summary: "Sap-sucking insects that distort new growth and, in some species, form protective lerps on leaves of native and horticultural plants."
type: article
keywords: [Psyllids, Psyllidae]
---

# Psyllids

> Sap-sucking insects that distort new growth and, in some species, form protective lerps on leaves of native and horticultural plants.

*Psyllidae*

Psyllids, also called jumping plant lice, are small sap-sucking insects in the family Psyllidae. Most species are host-specific, meaning particular psyllids are usually found only on one plant genus or a closely related group, such as leucaena psyllid on Leucaena, lilly pilly psyllid on Syzygium, tea tree psyllid on Leptospermum and Melaleuca, and spotted gum lerp psyllid on Corymbia species. The tomato potato psyllid attacks solanaceous crops and is a notifiable pest in parts of Australia due to its association with a serious plant pathogen overseas.

Adult psyllids are small, ranging from about 2 to 5 mm long depending on species, with a wedge-shaped body, clear or mottled wings held roof-like over the body, and prominent antennae. They resemble tiny cicadas and are strong jumpers, hence the common name. Nymphs are flattened, oval, scale-like insects found on the underside of leaves or on new shoots. Many nymphs secrete a white, waxy or crystalline protective covering called a lerp, which can range from a fine powdery coating to a distinct conical or shell-like structure depending on species. Nymphs feed by inserting their mouthparts into leaf tissue and remain relatively immobile under their lerp or waxy covering while developing through several stages before becoming winged adults.

Psyllids occur across most of Australia, with activity generally increasing during warmer months from spring through autumn when new growth flushes provide suitable feeding sites. Populations can build rapidly on susceptible hosts, particularly where plants are under stress or where natural enemies such as parasitic wasps, lacewings and predatory bugs are limited. Some species have multiple generations per year in warmer regions.

Management in commercial nursery and landscape situations relies on regular monitoring of new growth, encouraging beneficial insects, and maintaining plant health through appropriate irrigation and nutrition, as stressed plants and soft, vigorous new growth are often more attractive to psyllids. Pruning out heavily infested growth can reduce localised populations. Where chemical control is warranted, timing applications to target early nymphal stages before lerps or waxy coverings form gives better results, as the covering can reduce contact with sprays. Suspected detections of tomato potato psyllid on solanaceous crops should be reported to the relevant state biosecurity authority given its regulatory status.

## How to identify

- **Distorted or stunted new growth:** feeding by nymphs and adults can cause curling, puckering, yellowing or stunting of young leaves and shoots.
- **Visible lerps or waxy coverings:** small white, cream or brownish conical or scale-like structures on the leaf underside or along the midrib, often the most reliable sign of a psyllid infestation.
- **Honeydew and sooty mould:** some species excrete honeydew, leading to sticky leaf surfaces and black sooty mould growth, particularly noticeable on lilly pilly and related species.
- **Premature leaf drop or dieback:** heavy, sustained infestations can lead to leaf shedding and, in severe or repeated cases, dieback of affected shoots.
- **Field check:** turn over affected leaves and inspect the underside and along veins for flattened nymphs or their lerp coverings; gently tapping foliage over a white sheet or tray can dislodge jumping adults for easier identification.
- **Lookalikes:** lerp damage and honeydew can be confused with scale insect or mealybug infestations; scale insects are typically less mobile as adults and lack the jumping behaviour of adult psyllids, while mealybugs produce a more diffuse, cottony wax rather than the distinct lerp shape typical of many psyllid species.

## Registered products we stock

- [Transform | Isoclast Active | Insecticide](https://fernland.com.au/transform-isoclast-active-insecticide/) — Corteva
- [Initiator Systemic Plant Insecticide & Fertiliser Tablets](https://fernland.com.au/initiator-systemic-plant-insecticide-fertiliser-tablets/) — Envu
- [Crown 225SL Systemic Insecticide](https://fernland.com.au/crown-225sl-systemic-insecticide/) — ICL
- [Spectrum Systemic Insecticide 200SC](https://fernland.com.au/spectrum-systemic-insecticide-200sc/) — PCT SureFire
- [Stealth Miticide & Insecticide](https://fernland.com.au/stealth-miticide-insecticide/) — PCT CroPro
- [Tempo Xtra Turf & Ornamental Insecticide](https://fernland.com.au/tempo-xtra-turf-ornamental-insecticide/) — Envu
- [Contendor | Insecticide](https://fernland.com.au/contendor-insecticide/)

## Image credits

- [Photo: Didier Descouens via Wikimedia Commons (CC BY-SA 4.0)](https://commons.wikimedia.org/wiki/File:(MHNT)_Glycaspis_brimblecombei.jpg)
- [Photo: Matankic via Wikimedia Commons (CC BY-SA 4.0)](https://commons.wikimedia.org/wiki/File:Eucalyptus_Lerp_psyllid.jpg)
- [Photo: Jean and Fred from Perth, Australia via Wikimedia Commons (CC BY 2.0)](https://commons.wikimedia.org/wiki/File:A_different_lerp_(3634287187).jpg)
- [Photo: Lucas Lauretto via Wikimedia Commons (CC BY-SA 4.0)](https://commons.wikimedia.org/wiki/File:Caradocia_sp.jpg)