Have You Heard of the Green Headed Leafroller? 

Well, these little caterpillars really are a menace - especially for those orchardists who are trying to sell avocados. 

This is what it looks like.

And if you know the life cycle of caterpillars, you will know what they change into next. And look what they do to the leaves then.

I have been helping to place the leafroller moths in some avo orchards. We had to tether the moths to a staple on a piece of paper. The moth could not go anywhere. These moths were all females. 

Not long after the female moths emerge from their cocoons they lay eggs. So we place the moths in the trees to attract the male moths that may be there already. The females give off pheromones which is a lovely smell to the male moths.

When we collect the plastic containers with the moths again, we can put the eggs under a microscope and see whether the eggs have been fertilised and then we will know whether there were any male moths in the orchard.

So how are the moths tied up? First I had to catch them and put them in a small plastic container with a lid. Then I had to put them to sleep so that they would not fly away by giving them CO2. This is the gas we breath out. 

Catching the tiny moths.

Giving them 20 seconds of gas. If they are gassed for too long, they die and not gassed enough, they wake up while someone is trying to tie a cotton strand to a wing.

Equipment needed to do the job. Scientists are very inventive and use everyday things to do their experiments.

 Tying a strand of cotton to the moth's wing.

Tethered moths waiting to be stuck inside plastic triangular prisms and hung on branches. 

Packing containers in the 4x4 utes to take to the orchards.