“Many of our coconut palms that have been here for more than 30 years are suddenly dying”, starts this reader in her submission regarding the palm tree and the associated worm-like creatures pictured below. “The man that trims the fronds and fruit took the attached photos. The critters look like caterpillars and maybe something that is larvae. The creature with the stripe on its back almost looks like a millipede of some sort, maybe? It’s not clear if the creatures have created the problem OR there is some other problem which the critters are taking advantage of for their reproductive pleasure. I am located in Hawaii on the island of Hawaii.”

Firstly, we want to thank our reader for the excellent photos. We’ve only included three of the best or most relevant ones, but she sent quite a few that show the worm-like creatures below in various parts of the tree or the soil, as well as other photos of the supposed worm-made hole seen below. These photos really help us get a visual of what is going on, and, of course, helps us identify the worm-like creatures. Secondly, there is a lot to unpack here, so we will take this one issue at a time.

It is definitely strange that the palm trees are suddenly dying, considering they should only be middle-aged. There are other possible reasons than a worm/larval infestation for why a palm tree’s health could be degrading, such as fungal infections. However, given the holes in the tree, it does look like something is boring into the tree, which can definitely cause issues like the one our reader’s trees are facing. Additionally, we agree that the worm-like critter with the stripes on its back looks like a millipede, and we think that’s exactly what it is. These are not to be worried about. They will not be contributing to the trees’ decline: they are likely just there because the tree is dying, and thus rotting, which presents food for the millipede, who scavenges for dead things to eat.

When it comes to the other, translucent, worm-like creature, we think this is some type of larva: probably a caterpillar. It looks like it could be a palm flower caterpillar in its early stages (before it turns pink) or a ‘palm leaf skeletonizer’, but neither of these species bore into the trunk of the trees, they just feed on the leaves or buds. There are species of caterpillars which bore into the flowers of the palm tree, like the spathe borer, but not into the trunk. In any case, we think it’s best for our reader to consult a professional to deal with this infestation, given the dire state of the trees.

To conclude, we think both millipedes and caterpillars are infesting our reader’s trees, though the millipedes will not be doing any damage, and we don’t know exactly what caterpillars could be infesting the tree. It should also be stressed that it is not necessarily the caterpillars that are causing the death of the trees. It could still be some other type of non-worm-related problem that we would not be able to identify. For that reason, we think the best course of action is to consult a professional. We hope this helps, and we wish our reader, and her palm trees, the very best.

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