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What is eating my green buttonwood? I have included pictures below to show what I mean.

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I have seen what appears to be tiny black dots on the tree, but I haven't been able to get a great photo of them.

What can I do to get my tree back to good health?

The tree is planted in my yard, which is in South Florida. Thanks to the great users here for suggesting that I take a picture at night. I was able to get a good shot of the bug that is eating my tree.

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I ended up using sevin spray on the leaves and I put Diatomaceous earth on the ground below the tree. I haven't seen any weevils in a few days.

Ryan Gates
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When I saw your photos I immediately said "slugs". Or snails, depending on where you live. The roundedness (if that's a word) of the bite marks is the clue; that, and indications that the culprit nibbles mainly from the outside of the leaves, eats in irregularly shaped patches, stops nibbling after a short time, and doesn't skeletonize the leaves. Since you're asking here, I'm also assuming that you never see what's doing the eating, which also fits slugs and many snails, since they tend to feed at night or on cloudy/rainy days. Have you noticed shiny trails on the mulch, leaves, ground or any surrounding concrete in the morning?

The only thing that causes me to question my ID is that we're talking about a potentially large shrub here, one with presumably one or just a few trunks, but with a large amount of damage. Unless the slugs or snails are hiding out in the leaves, or the damage has been going on for a fairly long time, the damage seems greater than your average slug/snail infestation.

One way to confirm it's slugs is to set the lip of a shallow container even with the top of the soil/mulch near the trunk of the buttonwood, and then fill it with beer. Slugs like to party, so if they're around, you'll find them in the beer.

Jurp
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This looks exactly like vine weevil damage to me - in the States, I think it will be black vine weevil, and they leave these notched holes in the leaves, particularly at the edges. The trouble is, I'm not sure you're in an area where these are a problem (though it seems they are becoming an increasingly widespread issue) - plants in pots are more prone to vine weevil, but they can affect plants in the ground too. Their larvae eat through plant roots in the soil - further information here https://www.planetnatural.com/pest-problem-solver/lawn-pests/black-vine-weevil-control/

UPDATE; Great photo - so it is a vine weevil, but it's white vine weevil, a new invader to the States. Probably similar treatments to those recommended in the link I already provided to try to deal with it, but the best thing to do is contact your local Extension Service to find out if and what the latest and best treatments might be, they'll have up to date information, in particular regard to whether and which nematode treatments might be effective. Hopefully there is one that's effective, since they are the least environmentally damaging treatment - note that usually, nematode solutions are temperature sensitive and should only be applied when the temperature is appropriate for whichever one it is, so if you try one, follow the instructions that come with it. It's usual to order straight from the web, because there is only a short shelf life for these products, but see what the recommendation is from your Extension Service, as this is a fairly new problem. There may be no final solution to it though, it likely will require monitoring and treatment ongoing, unfortunately. I'll be interested to know what the Extension Service recommends.

I'll add the information link even though someone else posted it after I got you to check with a torch to try and find the weevil culprit... just in case you accept my answer and for future reference to others posing a similar question http://entnemdept.ufl.edu/creatures/orn/sri_lankan_weevil.htm

Bamboo
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  • The tree is planted in my yard in South Florida. – Ryan Gates Mar 05 '18 at 02:58
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    In theory, then, it shouldn't be vine weevil, but it certainly looks like it - if your temperatures are not very cold, go out at night with a torch - the adults feed at night and you should be able to find one or two if its those. Also more likely to find slugs or snails - but I'm not seeing any slime trails to indicate mollusc damage. – Bamboo Mar 05 '18 at 13:04
  • I uploaded a picture of the bug that is eating the tree. It does look like a vine weevil, but not the black kind. Is the link in your answer still applicable? – Ryan Gates Mar 06 '18 at 06:28
  • Ah well, there you go, I knew it was a vine weevil, but didn't know you got the white vine weevil there, will update my answer – Bamboo Mar 06 '18 at 10:12
  • How do I contact the Extension Service? – Ryan Gates Mar 06 '18 at 14:55
  • Well I'm in the UK and we have no such thing available here, but here's a link for you to work out which is yours and it has a list of phone numbers and addresses http://sfyl.ifas.ufl.edu/find-your-local-office/ – Bamboo Mar 06 '18 at 20:49
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This is the Sri Lankan weevil or Myllocerus undecimpustulatus undatus Marshall

Sri Lankan Weevil

The Sri Lankan weevil, is a plant pest with a wide range of hosts. This weevil spread from Sri Lanka into India and then Pakistan where many subspecies of Myllocerus undecimpustulatus Faust are considered pests of more than 20 crops. In the United States, the Sri Lankan weevil was first identified on Citrus sp. in Pompano Beach a city in Broward County Florida. Three specimens were identified by Dr. Charles W. O’Brien, first as Myllocerus undecimpustulatus, a species native to southern India, and then again as Myllocerus undatus Marshall native to Sri Lanka, finally as Myllocerus undecimpustulatus undatus Marshall to show its status as a subspecies.

Florida distribution

Figure 2. Distribution of Sri Lankan weevils, Myllocerus undecimpustulatus undatus Marshall, in Florida based on initial collection from 2000 to 2006, and additional data through 2012. Map created by Anita Neal, University of Florida.

http://entnemdept.ufl.edu/creatures/orn/sri_lankan_weevil.htm

As insecticide recommendations and regulations are updated yearly, it is advisable to consult a local Extension Service office or a pesticide reference guide for current information on control methods for this pest.

Graham Chiu
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