With Spring upon us, it is time to be vigilant with the cycle of pest and disease. Over the past 10 years, we have sadly seen the rapid increase of the Guava Moth, which arrived in our country from imported fruit and is now rampant.
The Guava moth is a small black and white speckled moth with a wingspan of about 15mm. The moth lays its eggs on the fruit’s surface and then the caterpillar burrows into the fruit. The caterpillar is a pinkish colour and grows to about 7mm in length.
It is not fussy and can lay its eggs on citrus, loquat, plums, pears, feijoas, guava, peaches and nuts. The caterpillar feeds inside the fruit leaving brown patches inside the fruit and can cause early fruit drop before it is ripe and sometimes making the whole fruit inedible. From the outside it is very hard to see but if you look closely there is a pin prick size hole. Honestly, I think I have consumed many of these in the past, as I am one just to munch the fruit first without even looking!!!
There is no actual cure for this moth at the moment, however actions can be taken.
Option one: Netting
Place a micro netting over your tree when the fruit is green to prevent the moth laying the eggs on the fruit. It can be a pain but is a good option of you want your fruit to be bug free. I am now experimenting with keeping mine and my clients’ fruit trees small so the netting process is a lot simpler. Another tip is to espalier your fruit trees, which makes netting a lot easier.
Option two: Pheromone traps
Some people buy pheromone traps, however not only are these expensive, they generally don’t decrease infestations.
Option three: Solar lights
Some of my clients have had successful trials with solar lights. You will need to be able to make a hole in the side of the plastic part of the solar light and pour some oil in there. How it works is that when the light comes on at night, the moth will fly in and get trapped. The downside to this is that all moths will fly in – not just guava moths, compromising the bio diversity of the area.
I will continue each year to do experiments on fruit and nut trees to see if I can establish more efficient ways for control, but for now, it is the netting solution for me.
My final tip is to make sure you remove rotting or infected fruit from the ground and either dump it or bury it, as this will destroy the pupating moths.
Good luck – and Happy Gardening!