Young, fresh mango leaves bursting from a tree are a glorious sight. Each a lovely lanceolate shape with a light, bright colour that collectively promises of gorgeous fruit to come. Thailand at its best.
Young, fresh mango leaves neatly snipped off at the base and lying scattered on the ground are a horrible sight for a gardener to wake up to.
It took me a while to work out what was doing this devastating surgery but the internet finally pointed its finger at the mango leaf-cutting weevil (Deporaus marginatus) and a careful search around our young trees found the little f...beetles. At only about 5mm long they are hard to spot.
Apparently, the females lay an egg on the leaf, cut it off the tree, then the larvae feed on it until they pupate in the soil. In an adult female's 2-3 months' life she can lay around 600 eggs, so that's 600 leaves lost. And that is the problem. We have plenty of caterpillars taking a small share of leaves that the trees can deal with but these tiny weevils are so destructive. A dozen could happily sit together on my fingernail and yet they could easily strip a mango tree of any new leaves.
Those leaves, that look like they were cut with scissors, get disposed of. I crush them between my palms, breaking them into tiny little pieces and squashing whatever may be attached. For good measure they often also get thrown into the pond. I fear no weevil but the hordes of the next generation are a different matter. Then I smell my hands. I'm sorry to lose these leaves but I can at least enjoy their lovely fragrance.
Some days a hundred leaves are snipped to ground. It brings out the hunter in me. I could probably spray something but prefer not to for the sake of the others. These trees have ants, spiders, flies, shieldbugs, ladybugs, praying mantids, moths, butterflies and much, much more. Stop to look for tiny weevils and you see these others. They are welcome. Some may cause a bit of damage but within the bounds of what I judge fair. But the tiny, tiny weevils are taking too much. This has to be a selective war, so I hunt.
Catching them is tricky. It starts by standing back a little and scanning for them. As long as they aren't hiding behind leaves they can be spotted with practice. Then comes the creep where I slowly get myself and my hand as close as possible. Finally comes the pounce where I pinch the leaf between my fingers and thumb as quickly as possible. Just like a leopard hunting gazelles really. But they are very quick and can either fly off before my squeeze or simply drop off the leaf and disappear. Sometimes it is possible to watch where they go, always to another young leaf, and get a second chance but they are even warier then. I manage about a 50% success rate.
The dark smudge on the leaf is the shadow of a weevil
The mature trees suffer less so I only hunt on the young ones where I can reach most leaves. Twice a day for over a month for as long as the mango trees have vulnerable leaves. The weevils still get a lot but I manage to keep on top of them so the trees aren't knocked back too much.
The interesting thing is that I really enjoy this game of hunting the weevils and end up spending more time doing it than I need to. Perhaps it's a kind of blood-lust (hemolymph-lust?) but I prefer to think of it as simply going back to basics, I am not relying on anything beyond my physical ability to find and catch. There may well be a more effective way of dealing with them but hunting weevils by hand gives me surprising satisfaction in this age of letting technology do the work.
