Non-pest insects can be confused for pests
Native wood boring moth
- Pithara
David Cameron (Farmanco) has reported of a very pink caterpillar found by a farmer near Pithara. It wasn’t found feeding on crop plants, but there was some concern that it survived a spray of Pyrinex Super (chlorpyrifos 400g/L and bifenthrin 20g/L).
DPIRD taxonomist Andras Szito identified the caterpillar as one of the many native wood boring moths belonging to the family Cossidae. There are so far 97 species named but many more awaiting discovery and description. Unfortunately most of the immature stages - even from the known species – remain undescribed. Andras noted that in this case the pink caterpillar may well be developing in a piece of root remaining in the paddock soil for decades.
For more information on Cossidae caterpillars refer to the Atlas of Living Australia.
Springtails
- Wickepin
Hilary Wittwer (Planfarm) reports of springtails in a feed crop near Wickepin. They appeared after recent rainfall and not much clover was left in the paddock. The grower was worried that they could be a pest causing damage.
These types of springtails, called Entomobryids, belong to the order Collembola. Although they are in the same group as the pest lucerne flea, they are not a pest and feed mainly on decomposing organic materials, especially fungi, helping to break it down.
They are wingless insects with antennae on their heads, three pairs of tiny legs and a springing organ on their underside. This acts as a defensive organ, allowing springtails to evade predators and flicks them quite large distances. They have softer bodies than other insects and this makes them vulnerable to desiccation. They react to dry conditions by going into a state of suspended animation or survive as drought-resistant eggs.
The forked springing organ can be seen on the rear of the body behind the last pair of legs.
Springtails live in air-filled pores, mainly in the top 10cm of soil, in the leaf litter layer, dung pats, compost heaps and any rotting animal and plant matter.
They can occur in very high numbers. Heavy rain flushes springtails out of their air-filled pockets in the soil.
For more information on springtails refer to the CSIRO Collembola: springtails page.
How to identify insects
Growers and consultants can use the PestFax Reporter app to take clear, close up images of unknown insects found in crops and pastures, and plant symptoms if applicable, and request a diagnosis.
DPIRD has a range of trained entomologists and taxonomists to assist growers and consultants with identifying insects.
Incorrectly diagnosing a non-pest insect as a pest may result in unnecessary spraying if there are no other damaging pests present.
For more information and tips on identifying insects refer to GRDC’s I SPY manual.
For more information contact research scientists Dustin Severtson, Northam on +61 (0)427 196 656 or Svetlana Micic, Albany on +61 (0)427 772 051.
Article author: Cindy Webster (DPIRD Narrogin).