Hi, my name is:  Thrip

I infect a wide variety of plants by sucking sap from leaves. There are around 6000 different species of this insect and many target commercial crops but others infect home garden plants.  In Australia, around 35 species cause plant damage and multiply much more rapidly as the weather warms up.

Describe yourself: About 1 – 2mm long, sometimes white and yellow but don’t mind black. Quite slim, with lovely fringed wings! Don’t be fooled, what I lack in size I make up for in tenacity. I’m very social and usually travel with lots of mates.

Hobbies: Laying eggs in unopened flowers, sucking sap, spreading viruses from plant to plant.

Likes: Most plants, but really fond of tomatoes, beans, roses, azaleas and fruit trees. I love any white or light-coloured flowers!

Dislikes: Soaps – like home made chilli soap, or store bought stuff. Don’t get along with Ladybirds or Lacewings.

You’ll know you’ve met me when: Your plants’ leaves look white and a bit mottled, the petals or fruit turn brown, and flower buds fall off! Late spring is my favourite time to visit your garden – just as the roses start to bloom!

If you want to dump me, you could try to:

  • Irritate me by putting a flattened square of aluminium foil around the base of plants to bounce light on the undersides of leaves.

  • Drench me with a forceful jet of water in the early morning for 3 consecutive days.
  • Spray me with a home made garlic or chilli soap. Or use a store bought insecticidal soap. And target the underside of leaves where I usually like to shelter.
  • Prevent my adult friends from emerging from leaf litter in the early spring by applying a thick layer of organic mulch around susceptible plants.
  • Remove damaged plant parts as I also like to over winter in plant tissue or bark fissures.
  • Hit me with a pyrethrum spray if I JUST WON”T LEAVE, but be careful not to use when friendly pollinating insects are visiting the same flowers!
  • Deter me by cultivating the soil around your plants in autumn to a depth of 6 cm and again in the following spring.
  • Destroy all infected flowers and buds but don’t compost them. Throw them out – and me with them!

Photographs:

Pic 1: http://www.dpi.qld.gov.au/cps/rde/dpi/hs.xsl/26_4282_ENA_HTML.htm
Pic 2: http://www.hort.uconn.edu/IPM/greenhs/htms/ghsemsg2007_07.htm Desc: Thrip damage on the leaf surface
Pic 3: http://www.bugsforbugs.com.au/product/41 Desc: Thrip predator mite… the mighty Montdorensis!