Western flower thrips, also interested in veggies!

Western flower thrips

Western Flower Thrips is a type of thrips common on leaf plants, flowers, and veggies.

Western Flower Thrips facts

NameFrankliniella occidentalis
OrderThysanopthera
Sub-orderTerebrantia

Danger – low, may spread fatal virus

Distribution: worldwide         –          Target hosts: over 250

This tiny pale-yellow thrips might contaminate your tomato plants with the fatal tomato spotted wilt virus. But for other plants, damage is mostly cosmetic.

Damage caused by Western Flower thrips

Key symptoms most certainly reveal an infestation of Western flower thrips.

Tomato Spotted Wilt Virus

Tomato spotted wilt virus - thripsA devastating disease is transmitted by Western Flower thrips as it feeds from one plant to the next.

A thrips that has fed on an infected plant at any stage of its lifecycle will infect all other plants it may feed on.

Many plants of the Solanaceae family can catch the disease if a contaminated thrips lands and feeds on them: tomato, potato, eggplant…

  • Other families can also catch the disease: Capsicum (chili and bell pepper plants) and lettuce will also suffer from this viral plant illness.

Symptoms of Western Flower thrips on plants

A colony of Western Flower thrips will result in cosmetic damage mostly. In some cases like vegetables or fruits, however, the harvest may be reduced in quality and quantity, too. The damage is similar to that of other thrips.

A few telltale signs are the following:

  • Symptoms of western flower thripssilver-white patches on leaves, these turn yellow-brown after while
  • black specks littered on the under and oversides of leaves.
  • As the white patches spread, leaves may start twisting and scarring.
  • On colored flowers, you’ll notice white spots on petals.
  • Of course, you might glimpse the tiny insects themselves.

As a result, ornamental flowers aren’t as beautiful. Fruits and vegetables are smaller and the harvest is less abundant, and they may even be scarred and unsalable.

  • It’s still safe to eat the harvest: thrips don’t cause toxins or poisons. At worst, the taste will be a little “off”.

Thrips will rarely kill a plant.

Western flower thrips host plants

Western flower thrips have been found feeding and/or reproducing on over 250 different plants belonging to many different families.

Host plants for Western flower thripsNearly all ornamental plants will at some point carry these thrips:

are among the most vulnerable.


Images: CC BY-NC 4.0: fffggg, kchang99
Public Domain: Jesse Rorabaugh, Scot Nelson