Banana Moths in South Florida

[palmislandRandy]

8 months ago I purchased a few palms from a well known South Florida grower (not Searle's). A 7 gallon Bentinckia condapana & a 5 gallon Dypsis nauseosa. The condapana immediately went in the ground & after 6 months never gained any size. I gently wiggled it one day & it just fell over. To my horror there were some larvea I later ID'd as Banana Moth around the rotted base. I pulled the roots & soil, then drenched the area with Imidacloprid.

I then noticed the newly emerging spear of the D nauseosa was browning & upon closer look there were larvae in tip of the spear, so I cut it off. It looked OK & grew for a few months, then recently the entire plant went down hill. Upon inspection, the base had larvae in the growing point. I've since treated my entire garden with systemics. My question is will these creatures spread & is the Imidacloprid enough of a deterrent to prevent any possible spread.

Sorry for the rambling post, but I'm concerned

-Randy

[BS Man about Palms]

Eeeww.. Good luck on that Randy!

[Jeff Searle]

Off the hook......

Sorry to hear about your loss. I can't really say I had this problem and can't really answer your question. Other than keeping a good eye on things and I would think the insecticide you used should be a good deterrent.

[PalmatierMeg]

Randy, thanks for the update. Don't waste money buying the Bayer watered down imadicloprid from the garden center. I buy 75% Merit powder and mix my own drench: 1/4 tsp of powder per gallon. One container of Merit (~$40) makes 100 gallons of drench. I treat certain palms regularly for white fly and Bizzie weevils. I get mine from a source in Punta Gorda and save shipping by picking it up. It may be easier to find on the east coast. Good luck on protecting your other palms.

[Zeeth]

I've had problems with those things before. Luckily they would just eat the emerging spears so they never killed anything.

[Dypsisdean]

I have recently lost some palms (and other plants) to these buggers. Apparently I have been unaware of their exisence here for many years and chaulked up several losses to other things because of the difficulty in identifying them as the source of the problem.

I have been doing extensive research - from ordering pheromone traps, and even capturing the larvae and testing different insecticides. And even talked to several of the biologists at several insecticide manufactorers. I can only report that what I am discovering is quite alarming, and I will be putting together a detailed article of my (and some other Big Island people's) experiences.

And for you SoCal guys - don't think this is only a tropical thing. They are now in SoCal. And my cooler location in Hawaii doesn't seem to phase them at all.

[Moose]

I got some stuff that should work for you Randy, you just didn't get it from me. And you will have the keep the dog inside for about three days.

Next time your down this way ...

[Kim]

This stuff scares me.

[BS Man about Palms]

I have recently lost some palms (and other plants) to these buggers. Apparently I have been unaware of their exisence here for many years and chaulked up several losses to other things because of the difficulty in identifying them as the source of the problem.

I have been doing extensive research - from ordering pheromone traps, and even capturing the larvae and testing different insecticides. And even talked to several of the biologists at several insecticide manufactorers. I can only report that what I am discovering is quite alarming, and I will be putting together a detailed article of my (and some other Big Island people's) experiences.

And for you SoCal guys - don't think this is only a tropical thing. They are now in SoCal. And my cooler location in Hawaii doesn't seem to phase them at all.

Awww POOP!

[palmislandRandy]

What's scary is the Bentinckia opened a new frond & looked great for 6 months as it was being eaten alive. Apparently once you find these on a plant, it's too late to treat. I hit my entire garden with Zenith 2F, a brand of Imidicloprid systemic & Bayers 3&1 (hose end sprayer). Fortunately, so far, the only victims were the two palms purchased from this source.

-Randy

[MattyB]

They're in CA? No!

[mnorell]

You say the B. condapanna was growing for six months while it was being eaten alive, but according to this UF info sheet, the life-cycle of these moths is only 1-1/2 months. They also primarily attack rotting/necrotic tissue. That would indicate that you most likely had a dead, dying or wounded palm that the moths got into, and you associated them after-the-fact with the death of your palm. I too had a B. condapanna that I planted and didn't grow much, and eventually collapsed, but I think it was just incapable of taking the South Florida climate. Perhaps the palms you bought were diseased or in some way stressed or wounded and provided a food-source for the usual array of decay-consumers, such as these caterpillars. Many "clean-up crew" critters get blamed for killing things when they arrived on the scene after the death process was initiated or completed, attracted to the smell of rotting tissue. And then everyone starts jumping the gun and using pesticides and causing more harm to the ecosystem, because it's a natural and easy assumption to attribute the problem to a visible consumer that we see afterward.

While the moths could have bored into living tissue, and even been responsible for effecting or hastening the ultimate demise of the palm, it is a secondary method of attack and that, combined with their short life-cycle, would seem a little suspicious as initiators, at least that's the way I interpret it. You should probably go to an entomologist and a plant pathologist for a firm diagnosis so you really get a handle on any diseases or other problems you might have. I would think that as long as you have healthy plants in your landscape, the moths should fly on to more attractive stomping-grounds.

These moths have been around in South Florida since 1963 and as that info-sheet says, they are at worst capable of getting a little out of hand in nursery situations. 50 years is a good long time to evaluate the danger of an insect so my own suggestion would be that you proceed in a prudent way to make sure you know exactly what's going on.

[kwtimo]

Randy, thanks for bringing this up. It seems as if we are always dealing with something. Whether it is banana moth, white fly, red palm mites, termites or some other critter, or fungal issues, soil deficiencies and so on. The learning curve never ends. I can appreciate what Mike had to say because I try to use organic, natural or biological products first, and only use the heavy stuff if I have to, and then at the recommended rates. Makes me wonder if making a periodic BT treatment would be a good preventative or treatment for the stuff that we just can't see until it's too late.

[palmislandRandy]

Both palms came from the same nursery, purchased at the same time. One went in the ground & the other was in the original pot. Coincidently these were the only 2 I've found that were infested. So far.

I've tried the natural route & living a half mile from the Everglades it proved futile Better growing through chemistry!

[Dr. George]

"You say the B. condapanna was growing for six months while it was being eaten alive, but according to this UF info sheet, the life-cycle of these moths is only 1-1/2 months. They also primarily attack rotting/necrotic tissue. That would indicate that you most likely had a dead, dying or wounded palm that the moths got into, and you associated them after-the-fact with the death of your palm. "

"While the moths could have bored into living tissue, and even been responsible for effecting or hastening the ultimate demise of the palm, it is a secondary method of attack and that, combined with their short life-cycle, would seem a little suspicious as initiators, at least that's the way I interpret it. You should probably go to an entomologist and a plant pathologist for a firm diagnosis so you really get a handle on any diseases or other problems you might have. I would think that as long as you have healthy plants in your landscape, the moths should fly on to more attractive stomping-grounds."

The above presumptive/deductive conclusions are logical, but not consistent with reality, at least not the reality of what banana moths are doing in Hawaii. Have been battling these buggers for several years now - in healthy palm trees - they do not fly very far, and often re-infest the same plant from which they emerged. I have one teddy that has had cycling problems with the moths for several years in spite of intense treatments.

Bt, systemic imadicloprid, trapping, spraying, entomogenous nematodes - have used them all individually and in combinations - still requires vigilance through regular inspection and individual plant treatment at the first sign of an infestation.

Please see a previous post on this subject: Banana Moths

Yes, if you live in an endemic area, one should be afraid, very afraid. This is a nasty problem, and vigilance is essential.

gmp

[Dypsisdean]

George and I just purchased a couple hunderd pheronome lures from Europe to help in monitoring and trapping these buggers.

The problem as I see it is that palms that you may assume just got bud rot, or just didn't thrive, on careful inspection can be seen to have these things in the roots, the trunk, or deep down in the crown. I have taken several and sprayed them with different poisons to experiment and placed them in a plastic bag with some plant material. And even though I knew there where several in the bag, I had trouble locating them as they burrowed in or hid among any folds. And if you can't find three that you know are in the bag, locating them in a palm is next to impossible.

So IMO, I don't think these are getting the "credit" for the damage they are doing.

[Mandrew968]

How big are they? I had some Clinostigmas, a while back that all crashed pretty fast--there were little worms in the pulled spears, but not very big at all...

[Dr. George]

How big are they? I had some Clinostigmas, a while back that all crashed pretty fast--there were little worms in the pulled spears, but not very big at all...

Size depends on the stage of the larva (caterpillar) - but not more than 1 inch long and maybe 1/8 inch wide. Have a characteristic brown head, and paired brown cross stripping down the back (check the pic's in the link in post #15 above). The frass (caterpillar poop) is characteristic - if you see caterpillars with brown heads and frass, its probably them.

They will attack spears just starting to open up and chew down the inside of the spear into the crown. When they are in the spear it tends to be earlier in their life cycle so those are a little smaller (and sometimes can't see the brown cross stripping down the back).

gmp

[Mandrew968]

How big are they? I had some Clinostigmas, a while back that all crashed pretty fast--there were little worms in the pulled spears, but not very big at all...

Size depends on the stage of the larva (caterpillar) - but not more than 1 inch long and maybe 1/8 inch wide. Have a characteristic brown head, and paired brown cross stripping down the back (check the pic's in the link in post #15 above). The frass (caterpillar poop) is characteristic - if you see caterpillars with brown heads and frass, its probably them.

They will attack spears just starting to open up and chew down the inside of the spear into the crown. When they are in the spear it tends to be earlier in their life cycle so those are a little smaller (and sometimes can't see the brown cross stripping down the back).

gmp

I took a look at your earlier thread and I am pretty convinced that they were banana moths. Thank you for the ID.

[mnorell]

According to this info-sheet from the University of Hawai'i on the dangers of this moth's larvae to Pritchardia as well as basically all other vegetation, it is again stressed that plants become vulnerable to the moth when they are stressed or damaged, and this includes pruning of palms, or for that matter just about any other plants. They are attracted to the smell and enter the cut petiole-end of palms, or any other wounded area. Also drought-stricken or otherwise struggling plants are vulnerable. The use of herbicides is also emphasized as a dangerous habit in gardens that may lead to infestation. So basically the message made is, don't mess with your landscape, or you may be sending an open invitation to these buggers.

[Dr. George]

According to this info-sheet from the University of Hawai'i on the dangers of this moth's larvae to Pritchardia as well as basically all other vegetation, it is again stressed that plants become vulnerable to the moth when they are stressed or damaged, and this includes pruning of palms, or for that matter just about any other plants. They are attracted to the smell and enter the cut petiole-end of palms, or any other wounded area. Also drought-stricken or otherwise struggling plants are vulnerable. The use of herbicides is also emphasized as a dangerous habit in gardens that may lead to infestation. So basically the message made is, don't mess with your landscape, or you may be sending an open invitation to these buggers.

That 10 year old info-sheet has some valuable info - yes, stress invites infestation, and needs to be minimized, but is not a requirement for infestation - these buggers will lay eggs on the spear of a healthy palm in the garden or potted in the nursery, and the caterpillars will munch their way down the spear into the meristem. The link in post #15 includes a pic of a spear from an otherwise healthy Lemurophoenix halleuxii in which we discovered a banana moth larvae early. The lemur remains healthy today.

We have lost innumerable palms in the nursery, that are on irrigation, have not been exposed to herbicides, and are not under stress. A palm does not have to be under stress to be vulnerable. Invariably the entry on these is through a healthy spear (or what the article calls "young heart leaves').

I have seen more than my share of banana moth infested palms and I have yet to see an entry through a cut petiole or a wound - I'm not saying it doesn't happen, but in my experience that is not a very common occurrence.

gmp

[Dypsisdean]

There is very little accurate information about this pest in the landscape. It was previosly thought to only be a "worthwhile" pest to fight in enclosed or monoculture farming like cane (sugar, dracenae, etc.)

But as mentioned, it is now only becoming recognized for the extent of damage it causes without receiving the "credit." It eats many plants, feeds on live and dead tissue, and is elusive to identification. I know Jeff Marcus is trying to get the Ag Dept. to recognize the actual damage this pest may be inflicting on many things without our knowledge.

[Dr. George]

Pics of Banana Moth larvae (caterpillars) and frass:

young and older larvae:

gmp

[Cindy Adair]

Very scary.