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Thrips

Common name: Thunder Flies

Related Links

Week Numbers

Chrysanthemum

Gladioli

Impatiens

Insecticides

Pea

Tomato

Top view of a Thrip

Western Flower Thrip
Overview:

Thrips are often abundant in flowers and on leaves during the summer months.

They feed inside developing flower buds and in the newly expanding leaves of plants.


There are a number of different types of Thrips, where each type can be be indigenous to a particular plant species.

Susceptible plants include: Chrysanthemum, Gladioli, Impatiens, Pea, Privet and Tomato.


View of tell tale signs of burrowing

Damaged Chrysanthemum Leaf

With the aid of a magnifying glass, these minute insects can be seen as long thin cigar-shaped insects in various colours of yellow, brown and or green.


They feed by burrowing into plant tissue of developing leaves and buds, where they suck the sap from plant tissue.

This can result in silver mottling of affected leaves and petals, and severe infestations prevent normal flowering.

Damage tends to occur outdoors from June to September,and as early as April in the greenhouse.


During the feeding process, it is quite common for viruses to be transmitted to host plants

They do not generally kill plants, but they can make them look limp / tired and often unsightly.


Translucent Larvae

Thrip Larvae
Life Cycle:

The adults lay their eggs on the leaf, and then the larvae emerge to feed on the plant growing buds and flower buds.

Young thrips (larvae) are similar to the adult, but without wings.

The very young ones are white, and the older ones yellow-brown.


The larvae live on the plant, but when they pupate the pupa often drops to the soil.

The pupae may hide on the potting compost for upto several months before the pupating adults emerge.


Visual Record

Yelloe Insect trap hanging from greenhouse roof

Yellow Sticky Card
Control: