Accused Palm Killer Photos Within

[Cindy Adair]

Warning: this topic is not for the faint hearted. 

But first one of my prized seed grown Pelagodoxa henryana palms in the ground more than a year trouble free.

On to the scary part.

Apparently in Puerto Rico identical holes in the ground can contain tarantulas or other creatures.

A few months ago a friend in more dry southern PR noticed a quarter sized hole near the stem of a young palm tree. He poured dilute dishwashing liquid into it and out came the expected tarantula. He poured sand into the hole and the palm seems fine.

I have seen many such holes on my current and previous farms in the wetter mountains at about 900 feet, but never associated any damage nor did they seem to be more commonly near plants. Neighbors told me they were nocturnal tarantula holes. I have seen a few tarantulas on my land and other places in PR, but not near the holes.

The holes on my current farm seem more common near the base of young palm trees below 4 feet tall. Filling them in with surrounding dirt does nothing as the hole reappears the next day.

I have begun to see mostly suddenly dying and dead palms this rainy season and always with one of these holes very close to the base. Sometimes spear pull first, but usually desiccation with browning of the newer leaves and quick demise.

I posted on PT but no one had noticed death by tarantula. 

 

Last night one of my trio of seed grown Pelagodoxa henryana palms (that had seemed just fine last week) looks awful.

Note the hole in the dirt near the base. So expecting a tarantula, this morning I poured more than half a gallon of Dawn diluted in water until I could see suds coming out. And within 2 minutes this beetle crawls out.

Later after capture, some rinsing and a photo session, here are close ups of the still alive beetle.

 

 

 

 

 

[Cindy Adair]

I moved next to a dying Heterospathe woodfordiana that had always looked a bit stressed which I blamed on too much sun. The spear pulled so I excavated some and poured the soapy water down the hole and lo and behold another beetle, bigger this time.

 

[Rickybobby]

Sorry to here Cindy. I guess spiders think they taste bad eh?

[palmsOrl]

Hmmm.  Seems like you found the culprit Cindy.  Perhaps a regular insecticide (which will cover beetles) drench around your small palms might be warranted.  I hate to kill anything, even insects, but I draw the line when they commit palmicide!

Edited August 3, 2019 by palmsOrl

[Cindy Adair]

I did a quick survey of maybe a dozen smaller palms and see more holes including some near healthy looking palms. I also excavated some holes and see the chambers beneath can be 1-2 cups in size. I saw no more beetles but ran out of soapy water in the volumes previously used and rain threatened far from my house.

They look most like rhino beetles but similar to ox beetles too from images on PT and Google.

 

 

I think burrowing a hole of substantial size could easily sever roots but also create a water trap which could easily lead to a deadly fungal infection. I do not see anything like the v shaped damage to leaves or holes in the trunks of big palms which I read could be caused by beetles.

Any ideas appreciated to confirm identification and treatment/prevention. Thanks!

 

 

[Silas_Sancona]

Would second the the referenced Ox Beetle as a potential culprit. For what Wikipedia is worth, it is described that the Larve ( Grubs ) will eat the roots of plants, inc. palms.  wonder if certain biologicals that kill the grubs would work on controlling these, if available there? 

Looking at acouple other pages, it appears this sp. also occures in the U.S. ( AZ- Florida, according to info on Bug guide )

Edited August 3, 2019 by Silas_Sancona
Edit

[Cindy Adair]

 

As to larvacides, I suspect I could get them and it could surely be needed to interrupt the life cycle. However as I see no larvae in the current holes I fear lots of rare small palms could die first.

I do expect insecticides would kill the adults, but I would love to try something to fill the hole first, as even if I kill the beetle with some noxious rain proof chemical the problematic burrow would remain. 

I was thinking of buying pea gravel or some other tiny rocks that our big box store might have. Then literally pouring the rocks into each hole until full. No idea if the beetles would even care.

But I could see if the hole recurs, as they did when I just shallowly topped with soil having no idea then how deep the spaces are.

The rain pouring down as I write is filling up those 1/2 gallon or more holes right now and none of my palms are true aquatics!

[The7thLegend]

The Rhinoceros Beetle looks very similar and is common in Florida, however I've never had a problem like yours.  I know Borax is helpful in pest control for insects like ants and beetles and safe to an extent, even beneficial in limited quantity for plants... BUT it can also have an adverse effect if overdosed.  I would probably fill the holes with dry native soil, less air and moisture.  Then an insecticide that creates a barrier around your palms or makes the environment unappealing is probably the easiest solution.

[Steve in Florida]

I believe it is Strategus oblongus  or Escarabajo rinoceronte, the Puerto Rican Rhino Beetle.

[Cindy Adair]

I found this interesting book online   Manejo integrado de plagas en cultivos de la Amazonía Ecuatoriana.

Thanks to all for your kind and thoughtful comments! Steve, I think you are right as my beetle doesn't look exactly like the coconut rhino beetle but seems to be the villain on my farm nevertheless.

I will keep a sharp eye out for evidence of the described coco beetle damage to adult trees.

I see silica warnings on the bag of small marble chips I just picked up today and thought perhaps that might desiccate a beetle while also filling the void and water trap created as they dig. I am still considering the variety of more specific options but the white color of the marble chips will also make it easy to spot palms where I have seen holes as I can top dress after hole filling.

If anyone thinks the above idea is dangerous to the palms please speak up now as I will start application tomorrow.

Please keep your comments and control suggestions coming! 

 

 

 

 

[Cindy Adair]

I have been away from my farm for a couple of days but will be checking the affected palms very soon.

I have read that diatomaceous earth is completely ineffective when wet (so not too great in the rainy season here) and that boric acid powder can be dangerous for plants.

I read here about something else that needs to be reapplied after rain.

2% Clove Oil; 0.6% Thyme Oil, 97.4% Other Ingredients (Starch, Sawdust, Granite, Wintergreen Oil) 

Ecosmart granules

However I wondered if the scent could perhaps remain longer if placed among the rocks underground. 

It seemed pretty nontoxic and granules might be easy to insert.  

Any thoughts on this crazy idea?

[BS Man about Palms]

Fascinating... I wish I could offer help other than wishing you good luck.

[GottmitAlex]

So, are they tarantulas or beetles?

[Kim]

 Oh,  the things we learn while growing palms! Good luck with your plan, I will be watching closely.

[Silas_Sancona]

18 hours ago, Cindy Adair said:

I have been away from my farm for a couple of days but will be checking the affected palms very soon.

I have read that diatomaceous earth is completely ineffective when wet (so not too great in the rainy season here) and that boric acid powder can be dangerous for plants.

I read here about something else that needs to be reapplied after rain.

2% Clove Oil; 0.6% Thyme Oil, 97.4% Other Ingredients (Starch, Sawdust, Granite, Wintergreen Oil) 

Ecosmart granules

However I wondered if the scent could perhaps remain longer if placed among the rocks underground. 

It seemed pretty nontoxic and granules might be easy to insert.  

Any thoughts on this crazy idea?

Not a crazy idea at all and wouldn't hurt to try.  If it helps to detur the adults from settling near the plants to deposit eggs, thats a good thing for sure.  Only thought is the scent would wear down quickly w/ all the rain this time of year there. Benificial Nematodes, if available there, might be a longer term solution to keep any grubs that might appear later on in check.  Won't hurt the seedlings / other plants at all.  

Agree w/ the disadvantages of Ditomaceous Earth. Tough to use here around the outside perimeter of the house since the walls get wet whenever i'm watering, or when it rains ...rephrase that, IF it rains lol.. Monster flying Cocokroaches we have here walk righ over it anyway. 

[Cindy Adair]

17 hours ago, GottmitAlex said:

So, are they tarantulas or beetles?

I am guessing (based only on two captured beetles each near a dying small palm) that all my holes near sick palms are dug by rhinoceros beetles.

However I do not doubt that some identical surface holes elsewhere house tarantulas. 

I have no idea whether tarantulas ever harm plants by digging. They could have tiny homes.

I have been told that in PR tarantulas are in larger numbers in the more dry areas,  but I have seen one out walking in the daytime on my wet farm and unearthed another while I was digging up a very healthy (but unwanted) banana clump.  I recall seeing only the spider while digging without any cavity as I see with the two beetles near my palms.

Today I saw a hole near the base of a (so far) healthy looking Cynometra tree (not a palm, but still special). I did not excavate the hole nor pour soapy water in it. 

[Cindy Adair]

Moving on to check a sample of my other palms, only one more hole had reappeared but it is next to my only Loxococcus rupicola in the ground about a year but 8 years from a tiny seedling.

To me the palm looks fine with a new pink spear but there's that scary hole! Again I sprayed this under $5 product in the hole and around the base.

 

 

Then I sprayed the rocks around all the "holey" trees.

It is likely to rain again tomorrow but it seemed another "first do no harm" kind of option.

[Fusca]

Thanks so much for posting this Cindy!  A couple weeks ago I had noticed the exact same hole adjacent to a juvenile Livistona decora that had completely desiccated.  Two days earlier I had watered it.  It looked perfect and did not notice the hole.  After reading the posts on the ox beetle (Strategus aloeus) I am certain that was the culprit even though I did not see the beetle.  I've seen black tarantulas here in Texas but their burrows are pretty shallow in comparison so I doubt that they would do much damage if any.  Now I'm going to track down some of that insecticide!

[Matt N- Dallas]

Sorry to see those Cindy!  We have a problem with rhino beetles in central and S TX.  I now keep all palms and agaves treated with systemic insecticide to prevent further losses.  They seem to have a special affinity for brahea and cocosoid palms at my place.  I’ve lost: sabal bermudana, brahea nitida, jubeaea x syagrus, butia, brahea decumbens, trithrinax acanthacoma, butia x jubaea. 

[Dypsisdean]

I don't think there is any doubt your killer is Strategus aloeus. Mentioned to escalate after hurricanes (due to all the downed trees) and peaks just before rainy season. Sound familiar? Further mentioned that they burrow underground and will come up under the base of young palms and eat the center out.

While doing some Google searches, PalmTalk comes up with several "hits." Searching for Strategus aloeus or Ox Beetle here brings up several more informative threads in addition to those already mentioned above and on Google.

There are even several on You Tube - some pretty creepy. Do a search there. Here's one to test your Spanish - apparently about another Beetle that eats the larvae of the Ox Beetle. This screen grab from that video confirms (for me) your enemy.

Now that you know what your enemy is, and that it is a major problem on young oil palm plantations, maybe there are some useful control methods being developed - although a quick check indicates there is not and easy fix.

 

 

[Cindy Adair]

Thanks for all the comments and help with research!

My beetles don’t have the grooves along their back, but wishful thinking that means they are less of a problem.

I still see no v shaped notches in any fronds of mature palms around western PR but maybe that will come later.

I suspect the beetles are not concerned about my marble chips and botanical spray, but it gave me something to do while considering other options.

I’ll keep you posted on further losses.

And I haven’t checked all my palms in the ground yet nor my palms in pots awaiting the perfect spot. 

Perhaps there are rhino killing/repelling  agents I should place in the planting hole, but too late for the dozen I planted last week...

[Dypsisdean]

Cindy - not sure what you meant by "no grooves along the back."  Strategus aloeus has no grooves. And I believe the v shaped notches you mentioned are usually from the Coconut Rhinocerous Beetle (Oryctes rhinoceros).

If you were talking about the beetle in the video (with the "grooves"), that is a predatory beetle shown eating the larvae of Strategus aloeus - a different beetle. Here is "your" beetle next to the S. aloeus.

[Jocam019]

Wow, I’m sorry for bypassing this thread but I was doing some heavy watering on a maple seedling I planted earlier this season and up/out came larva that look very similar to the pictures and videos posted on here. I’m left wondering if I’m going to deal with this bug as well; I’d hate to lose any palms! 

 

Are there any other beetles that linger around palms but don’t cause their death?

[Silas_Sancona]

16 minutes ago, Jocam019 said:

Wow, I’m sorry for bypassing this thread but I was doing some heavy watering on a maple seedling I planted earlier this season and up/out came larva that look very similar to the pictures and videos posted on here. I’m left wondering if I’m going to deal with this bug as well; I’d hate to lose any palms! 

 

Are there any other beetles that linger around palms but don’t cause their death?

Hard to say. According to Inaturalist, the ranges of both the Aloeus and Smooth Ox Beetle ( Strategus antaeus ) come real close to the Miami area and i wouldn't doubt you'd find them around if you looked. 

That said, the larve ( grubs ) of many ground dwelling beetles incl Chaffers ( those brown " june bugs" you see around outdoor lights during the summer ) and other Scarab -type beetles look like those pictured above. So, unless you see adults, its hard to say with 100% accuracy which sp. it is you're seeing.  Larve of many of the beetles that prey on grubs tend to look a bit different and ..if iremember correctly,  aren't as likely to eat the roots of palms, etc other plants. Some sp. also participate in pollination as adults as well. 

As big as these might be, back in CA. i was shown what i swear was the biggest " worm " i have ever seen after investigating the splintered trunk of a 50ft Live Oak that had come down earlier that day. Grub itself was 8" in length and close to 2" wide. Not sure what beetle sp. it belonged to though. 

[GottmitAlex]

Yikes. To tell everyone the truth, anytime a beetle lands on my narrow garden sliver: mortus est.

 

 

[Jocam019]

1 hour ago, Silas_Sancona said:

Hard to say. According to Inaturalist, the ranges of both the Aloeus and Smooth Ox Beetle ( Strategus antaeus ) come real close to the Miami area and i wouldn't doubt you'd find them around if you looked. 

That said, the larve ( grubs ) of many ground dwelling beetles incl Chaffers ( those brown " june bugs" you see around outdoor lights during the summer ) and other Scarab -type beetles look like those pictured above. So, unless you see adults, its hard to say with 100% accuracy which sp. it is you're seeing.  Larve of many of the beetles that prey on grubs tend to look a bit different and ..if iremember correctly,  aren't as likely to eat the roots of palms, etc other plants. Some sp. also participate in pollination as adults as well. 

As big as these might be, back in CA. i was shown what i swear was the biggest " worm " i have ever seen after investigating the splintered trunk of a 50ft Live Oak that had come down earlier that day. Grub itself was 8" in length and close to 2" wide. Not sure what beetle sp. it belonged to though. 

Well, this is comforting! 

It’s really Junebug galore here where I live; here’s to hoping what I saw was actually one of those. I’d hate to deal with these palm killing beetles. Thank you so much for that brief description!

[Silas_Sancona]

24 minutes ago, Jocam019 said:

Well, this is comforting! 

It’s really Junebug galore here where I live; here’s to hoping what I saw was actually one of those. I’d hate to deal with these palm killing beetles. Thank you so much for that brief description!

lol i remember those things well.. While we had plenty of them in Bradenton, and oddly enough, back in San Jose ( CA.) where i grew up, nothing compares to the amount of June Bugs you'd see  when i lived in Kansas.. things were everywhere and came out by the 1000's.. There would be layers of dead and dying beetles under the street lights in the neighborhod i'd lived in.. Great for all the Toads that would come out for dinner, pain in the rear when trying to keep 'em out of the house this time of year there.

Weird that Ox beetles are supposedly native here in the desert yet i have never seen any. One of the Hurcules beetle sp. are native here also but never see them either.  Palo Verde beetles however are pretty common ( except here at the house / in my neighborhood for some reason) Those things are huge and can inflict a pretty  nasty bite if handled. 

[GottmitAlex]

6 minutes ago, Silas_Sancona said:

lol i remember those things well.. While we had plenty of them in Bradenton, and oddly enough, back in San Jose ( CA.) where i grew up, nothing compares to the amount of June Bugs you'd see  when i lived in Kansas.. things were everywhere and came out by the 1000's.. There would be layers of dead and dying beetles under the street lights in the neighborhod i'd lived in.. Great for all the Toads that would come out for dinner, pain in the rear when trying to keep 'em out of the house this time of year there.

Weird that Ox beetles are supposedly native here in the desert yet i have never seen any. One of the Hurcules beetle sp. are native here also but never see them either.  Palo Verde beetles however are pretty common ( except here at the house / in my neighborhood for some reason) Those things are huge and can inflict a pretty  nasty bite if handled. 

I try not to digress,  however, when I read your first sentence i could not help remember the song from "An American in Paris"   "I remember it well." With Maurice Chevalier. 

 

[Cindy Adair]

8 hours ago, Dypsisdean said:

Cindy - not sure what you meant by "no grooves along the back."  Strategus aloeus has no grooves. And I believe the v shaped notches you mentioned are usually from the Coconut Rhinocerous Beetle (Oryctes rhinoceros).

If you were talking about the beetle in the video (with the "grooves"), that is a predatory beetle shown eating the larvae of Strategus aloeus - a different beetle. Here is "your" beetle next to the S. aloeus.

Dean, my earlier look at images on Google must have intermixed the predator (with the “grooves” ) and my invader.

I see you are entirely correct and no amount of wishful thinking will change the facts that my issues may quickly worsen.

And you are also right that the ox beetle is a different creature from mine. 

I can see that I need to learn much more to figure out my options, as bull dozing my palms (as was done on the video you kindly supplied) is not a happy thought.

Surely the oil palm plantation owners have some more ideas?

Thanks again so much!

I think I need a common name (for my use) that reflects my current feelings for this creature, but is acceptable around children.

Ideas welcome.

 

[Dypsisdean]

Sorry Cindy - I think I may have continued to add some more confusion. And please be advised, I do not claim to be an expert or know much about this topic other than some Google reading on a rainy afternoon.

From what I read, the Ox Beetle, the Texas Beetle mentioned in other topics here, and Strategus aloeus are one in the same. It is very common all through the Southern USA, Caribbean, and surrounding areas. There are many mentions of it eating roots of plants and especially targeting young palms (although several of those reports on the net originate from PalmTalk) - while most other rhino beetles seem to prefer decaying material.

Positive IDs are difficult because so many are similar, male and female are different, and color can vary within the species by age and location - and there are hundreds of species. In fact, the Puerto Rican rhinocerous beetle (Strategus oblongus) is identical to an untrained eye. However, it is reported to be rare, and there are no reports as to its eating habits - as there are with the Ox beetle and the identical behavior as you have experienced.

We had an outbreak of the Coconut rhino beetle here on Oahu and a scary future envisioned for the landscape of Hawaii. However, with pheromone traps and some vigilance, the battle is not lost. So with a proper ID (imperative) you can put up a good fight.

Other than effective chemicals I did read that this beetle seems to have an affinity for light (as do several), and can be seen surrounding outdoor lights in summer. I have a problem with Banana Moth here and use those outdoor bug zappers. The good ones claim to "cover" a large area, and the light is not bright (sort of ultra violet).  I put a bucket with some water and detergent underneath to make sure the stunned ones don't recover after falling to the ground. You would be amazed at what is out there flying around at night.

I found in my battles with Banana Moth that the best strategy is to kill the adults before they can lay more eggs, since the larval stage is so difficult to kill. Also, and I am unsure about this, but I think the adult is what does the burrowing and the damage eating the roots and the young palm heart. The larvae may live mostly on the decaying matter left over and in the ground. So, if you can find/kill some more adults and get a positive ID, they may have a specific pheromone for them. This can be somewhat expensive but effective and targets the adults as well.

And another positive - these seem to be only a problem with the youngest palms. So perhaps some screening on the ground surrounding your most precious palms (as shown in one PT topic) would help them get past this susceptible stage.

[Meangreen94z]

I moved into a rent house over the winter while I look for property. The backyard faces out to a mostly unmaintained field. Starting in June I faced an ongoing 2 month battle with multiple pests attacking/killing/damaging agave, cactus, palms, and potted trees awaiting my next home. I tried various treatments,  with little success. Finally when using Dominion 2L insecticide/termiticide as a systemic treatment the attack’s have come to an abrupt stop. I highly recommend it, if you find no other solution.

Edited August 12, 2019 by Meangreen94z

[GottmitAlex]

I've lost cocos nucifera myself.

Here's a song which I particularly like and I dedicate to dead palms we loved.

https://youtu.be/nopBvlKfYgY

Edited August 12, 2019 by GottmitAlex

[Cindy Adair]

What a great place online where I can get sympathy, humor and excellent advice! I am very appreciative of everyone's posts. Thanks especially to Dypsis Dean for all his research!

Today I made time to take the dead bugs to my closest USDA office in Mayaguez. The very helpful bilingual staff member offered to photograph the beetles and send the photo to an associated entomologist in Miami. However since the antemortem photos are posted here, I simply sent the link to this topic and hope to hear back from the entomologist in the future.

I just read this https://bioone.org/journals/Florida-Entomologist/volume-97/issue-3/024.097.0308/Comparative-Toxicity-of-Six-Insecticides-on-the-Rhinoceros-Beetle-Coleoptera/10.1653/024.097.0308.full written in 2014 which was helpful. Earlier today I bought some spinosad

which as it turned out was one of the least effective of the 6 products tested, but still more than 60% kill rate. They did not study which product stopped digging and eating and reproducing behaviors first.

Imidocloprid rated higher and as a veterinarian I am pretty familiar with it as the active ingredient in Advantage topical flea control. None at the store I visited today but likely elsewhere.

Of course I am concerned about killing bees, but underground in what I now know is called the beetle's "gallery", I would not think bees would wander about.

They are nocturnal so I'm heading out now to apply some and slow them down ASAP. 

 

 

 

[Cindy Adair]

I have heard back from the entomologists and after receiving their permission I will add more life cycle information. They sent the same paper I mentioned above regarding treatment but of course it only tested the six chemicals.

Alas I found a hole in a potted palm yesterday evening and all I had on hand was the organic clove oil based product but I sprayed it into the gallery entrance heavily.

It is not a rare palm and at least I can use it as a test of my products I guess. 

I have a sick friend here who needs transportation today, but may have time to duck into the big box store en route.

I must choose something in stock as they can not order to ship here. 

So my question to you today is one of safety to young palms if I apply the Bioadvanced tree dual action granules or liquid which has fertilizer too?

Nothing on line shows they will stock imidocloprid without the fertilizer but if they do I will choose that.

The company by phone claims it is safe on palms, but I’d rather hear from someone here.

I have applied no fertilizer to my palms once planted and hate to cause harm trying to help.

The idea as much as I still resist it might be to treat all my young palms (when I have time) rather than waiting to see the holes or symptoms of impending death.

Thanks for your thoughts!

[Merlyn]

When I bought Imidacloprid, I purchased a wettable powder called "Adonis 75 WSP."  I believe I paid about $25 for a couple of packs in a bag, though the current price I see is $39:

https://www.amazon.com/Adonis-contains-Imidacloprid-2-25-ADONIS/dp/B0195V1MD8

I opened one of the packs and poured it into a small jelly jar, and just scoop out small amounts to mix as an insecticide as needed.  A small amount will go a long way, I think it's something like 2 grams / gallon.  It may be something you'd have to order, but $20-30 for a lifetime's supply isn't bad!

[Cindy Adair]

Thanks so much to both of you who sent specific imidocloprid product recommendations. 

As you can read I have hated the idea of using anything.

In fact I planted out (far from other important plants) a scale infested caimito (star apple) that I did not inspect carefully enough before purchase here.

Isolation is always my first choice where possible.

I did not treat it at all despite eventually watching the secondary black sooty mold covering the leaves.

After many months I saw it perk up and looking closely it was fascinating to see the large white fluffy predator insects eat the scale in just a few days!

The Star Apple looks great now.  I am a believer in mostly letting nature work.

However, my attachment is stronger to these palms many of which are likely irreplaceable.

So my plan is to use the available Bayer “bioadvanced” granules on the otherwise doomed palms and the imidocloprid only product I just ordered when it arrives for all my others as a preventative. 

[HiwaKika]

On 8/10/2019 at 6:39 PM, Dypsisdean said:

Cindy - not sure what you meant by "no grooves along the back."  Strategus aloeus has no grooves. And I believe the v shaped notches you mentioned are usually from the Coconut Rhinocerous Beetle (Oryctes rhinoceros).

If you were talking about the beetle in the video (with the "grooves"), that is a predatory beetle shown eating the larvae of Strategus aloeus - a different beetle. Here is "your" beetle next to the S. aloeus.

Looks more like a Triceratops. I’d try a Triceratops trap or maybe Dawn makes a Triceratops scented dish soap.

[Cindy Adair]

Humor helps, thanks! 

I will pass on that I have heard from two fellow IPS Directors (whose names you would know) and both were unfamiliar with this issue, but concerned. 

So please continue posting if you think you have had similar issues.

If warranted, we might try to get an expert to write an article for PALMS or something for the newsletter.

[Ed Askew]

Ok I just found out about this thread, having waged war against this bug for years and having lost 20 or thirty palms to it.  This is the ox beetle, Strategus Aloeus.  It is found all over the new world.  It is the adults and not larvae that kill small palms, usually palms less than 3 feet tall.  They eat into the heart of the palm from underneath.  I have tried all sorts of things to prevent and to act against attacks.  Here’s what not to do: use insecticides, especially imidacloprid as mentioned above.  These beetles are scarabs.  So are some very important allies of the palm grower, lady beetles, that spend a lot of time in the area at the base of the palm and keep scale from getting out of control.  You may never see them unless you know what the immature forms look like and you get up early and go out with a magnifying glass looking for them, but if you don’t have a scale problem they are working for you.  

Here is what to do:  pile up 2 or 3 inch sized rocks, 1/2 cubic feet total, in a 12 inch diameter circle around every small palm.  If planting a new palm, leave 3 inches deep around the palm dirt free, I actually use a garden hose and wash potting soil off the top of the roots, and replace that with rocks and this thick red clay we have.  Note I have only done this with sabals.  You must pile rocks right up against the palm, as that’s where the beetle prefers to dig.  Leave weeds be, and consider planting a ground cover, as the beetles like nothing more than your nice manicured garden to march around in.  Nothing is 100 % effective, but this helps.  I have an armadillo problem.  I admit to slaughtering vast numbers of armadillos in the past, but have learned to leave them alone until beetle season is over which is between June 1 and August 1 normally in Mississippi.  My armadillos have found out about these beetles being around my palms and they are taking them out for me.  We have come to terms.  During beetle season, make rounds every day and when you see a hole fill it with water, turn the water off, as it goes down squirt a little dish soap in the hole.  Fill it again, then turn the water off and walk away.  Stealthily sneak back 5 minutes later.  Likely you will catch the enemy trying to escape.  Have a stick handy and get him out.  You can pick them up, as they won’t hurt you.  If it’s a female, there’s still a male in the hole.  Flush the hole out until you have him.  It might take 45 minutes.  Fill the hole with clay with rocks at the top.  I use 1/2 inch rebar to pack the hole.  You will find they are 20 inches deep.  If you get the beetle out in time your palm has a really good chance of surviving.

[Ed Askew]

I don’t know if I made it clear but I would suggest you never use imidacloprid on or around a palm.  I would not use any insecticides at all, but there is probably nothing worse than using a systemic.  I say this because I have made that mistake.  What happens is that you kill scale enemies.  You can’t kill all scale with insecticides, and if you kill their enemies, you will see an explosion of scale as I did that took years to finally get under control.  Insecticides, unfortunately, are not the fix for what is a very difficult problem.