Adult Guava Moth
Guava moth is becoming the bane of most fruit grower's existence. I have had them for the last two years in a couple of my old feijoa trees and the fruit has just gone to waste.
This year I am finally being proactive and doing something about it. I certainly don't want it spreading to my plum, peach and guava trees.
Here's a bit of information on guava moth.
- It is well established in Northland and has made its way down to the Waikato over the last year or two. It was first discovered in Northland in 1997.
- They attack a wide variety of fruit, such as feijoas, plums, guavas, peaches, nectarines, macadamia nuts, lemons, mandarins etc.
- Female moths lay their eggs on the fruit or adjacent leaves and, upon hatching, the larvae burrow into the flesh causing considerable damage and loss. They are very hard to spot at this stage as they leave only a tiny pin prick size hole as they go in.
- Guava moth can breed all year round as there are so many different types of fruit they infect. They can build up to quite large numbers if not controlled.
Have you got guava moth already? What to look out for.
- Check for immature fruit drop, fruit will often drop before it is fully ripe.
- Check windfall fruit regularly for markings, such as exit holes, small discolouration or bruised looking fruit
Killing those little blighters!
Hard to do. Using several methods is your best hope of controlling the population
Pheromone Traps - work by replicating the pheromones produced by female moths in order to catch male moths. This will also give an indication of infestation and tell you when to spray.
Neem Oil - Spray your diluted Neem oil all over your fruit trees, taking care to spray all the fruit. Best done when your trap shows the moths are present, and when the fruit is developing.
Neem granules - Sprinkling Neem or Sea-Hume Granules around the drip line of trees, especially where the fruit is falling. This will help control the larvae stage of the guava moths cycle.
Removing infected fruit - Remove rotting fruit from the ground and dispose of it and mow regularly beneath fruit trees. This is effective because the moths pupate in the leaf litter and fruit pulp (or so we believe). Avoid composting fallen fruit as the moths can complete their lifecycle in some compost systems.
Covering your Fruit - Cover the fruit or the entire tree with fine netting as the fruit first starts to develop. Fruit only becomes infested with the larvae if the moths can lay their eggs on the fruit. Don't cover the tree during flowering as the flowers won't get pollinated by bees, birds or other pollinator insects.
Biological Control - As the larvae tend to pupate close to the soil surface, chickens may well be helpful in reducing the numbers.
Oil/Solar traps - There has been success with homemade solar lights that have been made into oil traps. There are examples of them online if you Google them.
For best results, it's worth talking to, and working together with neighbours and your local community to really get on top of the problem.