Lethal Yellow - A Few Questions


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Thank goodness I haven't had to worry about Lethal Yellow in the two locations I have grown palms. So I don't know as much as I should.

My question is prompted by the comments I constantly hear about the beauty of Beccariophoenix, and how it could easily replace the coconut as the symbol of the tropics if lethal yellow ever destroyed them all.

Is there any way of knowing which palms are affected by lethal yellow before experimenting? Is there a common thread that would alert someone if a species is susceptible. For example, are all coccoid palms affected by lethal yellow? Are Jubea and Jubeaopsis affected? They are both coccoid palms, but I don't know if they "cross paths" in areas where they may acquire lethal yellow. If one palm in a genus is affected, does this mean they all are? Are some palms completely immune, or is it just a degree of resistance?

So, are there any clues to indicate if Beccariophoenix could ever take the place in resorts and tropical locations that would look naked without coco palms, if lethal yellow or something else would make them undesirable.
Hey Dean,
We in Vero had a bout of phytoplasmic lethal yellowing back in the mid '80s. All of the Jamaica tall Cocos were wiped out. The protocol was to use maypan in their stead. I will ask some of the guys who know their thing around here some questions today with regard to resistance and vector mitigation. It's been some time since the concern for lethal yellow was on the front burner here, but as I recall there were some common crownshafted palms that were on the hot list for occlusion during those times. I will get some feedback to you regarding our trials here. And I will try to get a list of what was affected back then. I hadn't moved to Fla. until the late eighties. With regard to Beccariophoenix and the landscape industry, my first thought is the liability of falling coco-bombs would be a non issue with Becc..
The only negative That we in Vero have little imperical evidence to work with is cyclone damage. Becc. is not from the cyclone belts and it will be interesting to see how they fare in high wind events. We have some tall madagascariensis here but the sp. no window and alfredii are all still new to the scene in our neck of the palm grove.
I just pulled out Ornamental Palm Horticulture, by Broschat and Meerow. They have a list of susceptible species. In looking at the list it seems to dance in and out of cocoseae. It hits Pritchardia, Livistonia and Phoenix to one degree or another. More to come... -Justin
If I'm remembering correctly, Howea is also on the list of the Ag. Dept. to check for lethal yellowing. I don't know if that's a general thing they look for in all palms or not.
Thanks Justin,

I know Hawaii is fearful that lethal yellow could hit us hard, with all the coconuts and Pritchardia. So I was curious as to if there was anyway to predict which palms would be affected. Or if there is any common thread as to what makes a palm at risk. If certain cocos are, and some are not, then I am guessing there is no way to really know ahead of time.

Regarding the Beccarios: Jeff Marcus believes as you have mentioned, that the advantage of no falling coconuts is major. The cost to keep tens, if not hundreds, of thousands of coco palms trimmed is a considerable expense. I was unaware if Beccarios were in or out of the cyclone belt. Is it only northern Madagascar that gets hit with them? I thought I remembered seeing one coming ashore around mid-island one time. But I could be wrong.

While checking I see the town of Morondava was hit hard Jan 20, 2009. This looks close to where the Beccarios are, or am I wrong? At any rate it said 7 cyclones hit the island in 2007. Most to the north I would imagine. But here's a map of where Morondava is. It appears as if this is the area where the baobabs are. Check HERE for some great pics of the baobobs I came across.


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During the southern hemisphere's most recent or current cyclone season in the Madagascar region I recall seeing a report on the weather channel indicating that there was a cyclone off the east coast of the island. I don't know if it made landfall. I'm sure they have some incidents with cyclones, but maybe (?) not as much as the carribean basin or northen Australia and Mexico's west central coast. Dosen't Madagascar have a cold water current flanking it to one side or another?
We were hit three times by hurricanes in thirteen months, a few years back and our Beccario's pulled through fine. One was knocked to the ground and re-grew just fine. During those three storm events with Jean being the worst with cat three+ winds, I noticed a big difference in palms from storm areas versus others. My Caryotas and Syagrus were in bad shape. My chamaerops perished. I know this dosen't mean much, but there has to be something to the notion of cyclone tolerant species. To get around to answering your question Dean I don't know whether the Beccario evolved in cyclone country. But if I were to invest the money in giving Cocos a run for landscape analog, I would make sure Beccario can pass the bar or milibars as it were. -Justin
And to answer MattyB, the book I have lists both Howea as vulnerable to lethal yellow.
Okay, With regard to cyclones and Madagascar I stand corrected. And mea culpa, for not checking facts before making a flat statement. I just read a nice blog by Dr. Steve Lyons on the Weather Channel's web site. He noted that there were 38 cyclones that impacted Madagascar in a recent ten year period. The U.S. mainland by comparison sustained 46 storms in the same period. So it is very likely the costal form af Beccariophoenix has met with these conditions. The cyclones occour from October through May. They move from east to west riding in from tropical Indian ocean steering patterns. I would imagine the worst of the storms are blunted by the landmass if they arrive on the east coast, and work their way through the mountains to the west coast; from where it would appear the costal forms come. The image in the Dr. Lyons blog shows a well formed storm in the channel between the continent and Madagascar. Back to lethal yellow for a moment. A friend was telling me that the full fury of the mid eighties outbreak never made it past Martin county, some thrirty miles south of us. So I guess the Jamaican Cocos just froze to death in that time period. The vast majority of our Cocos here are Maypan.
On an ethnobotany note for Beccariophoenix, I read today that the endemic population of costal forms are used, by way of flower or fruit to make a beverage. The book didn't state whether it contained alcohol or not.

Thanks again for the info. Maybe someone with a larger Bec. that has been hit with a cyclone lately will see this and chime in.

I am fairly certain that at least the northern third of Madagascar gets hit regularly. I'm not sure about the southern half. Also, I haven't yet looked to see where the majority of Becs. are from.

But it sure would be nice if they are hurricane and LY resistant. As I would assume I'm not the only one that would miss the coconut look in the tropics. :)

Jeff Marcus may be coming over tomorrow. He is hot on the idea of Becs as a "stand in" for Cocos in all the resorts around here due to the coconut falling issue. So I'll ask him some of these things.
Hey Dean, I just cracked open the revised Genera Palmerum (what a beautiful book), to see the illustration of Beccariophoenix distribution. The shading on the map of Madagascar shows the distribution confined to the lower two thirds of the east coast of the the island. The middle of the range of distibution spreads well inland. Seeing this furthers the support for this palm being exposed to cylonic activity. Again, contrary to my supposition. We are in the process of putting together an order for Jeff Marcus. Mention the crazy Native Habitat boys from Vero and He'll know of whom you speak. We've tried to throw our business his way over the years. Didn't Jeff dub the Bec. the Madagascar coconut? Speaking of vendors did you get a chance to see Tobias' Dypsis arenarum pics, in his archives? Take care -Justin
I have attempted to do some reading on LY throughout the Internet. It is disarming to see it's apparent resurgence again in Jamaica and spread to Guatamala and Honduras. I also see it's spread to Sri Lanka but do not know if the mass destruction of trees in that region was sucessful. Hawaii will most likely be protected by it's remoteness.

One article that I found interesting suggested that the insect responsible for the spread of LY arrived at a latter date through cattle imported to the West Indies in the late 1700's. Actually not the cattle but rather the plant material to feed the animals on the boats transporting them from India and Africa. According to this article, coconuts were introduced to the West Indies in the early 1600's with no problems until around 1800.

I personally experienced the ravages of LY in South Florida. The annihilation of coconuts by LY in Florida commenced in the Keys in the 60's spreading to the Palm Beaches in the mid-70's. Beautiful 60 foot tall Jamaicans were destroyed in 6 months. The Town of Palm Beach was the first I know to establish very quickly a plan of anti-biotic innoculation. While many Jamaican Talls were lost, today I am certain that well over 1,000 exist today on the island alone.

In Florida, coconuts are strictly for aesthetics. In contrast, numerous locations in the West Indies depend on the coconut for economic survival. The expense of innoculation($70 a year per tree) is prohibitive.

The coconut(previously the cocoanut) arrived in Palm Beach around 1879 with the wreck of the Spanish Galleon,the Providencia, which dumped 20,000 coconuts onto the beach which thrived. But for this, Henry Flagler would not have seen charm in the area that he attributed to it's coconuts. Beyond that, it is doubtful he would have invested with the feverish intensity that he did.

The coconut is irreplaceable. Sadly, there is simply no substitute. The Window Pane Palm is slick but it does not hold a candle. This is a serious problem that needs attention!
Hi Bubba, I haven't poured over much published work on LY, either on the ineternet or in books. Did you find anything that relates to work being done to defeat the problem?
While I agree with you that the cultures on the islands stand to lose more than we in Florida, I will argue that strictly aesthetic carries a huge weight in our regional economy. You posited yourself that had Henry Flagler the tourist not seen a wealth of Coconuts gracing the landscape in P.B. county he may have passed it up for another destination. I can't imagine the way our area would have turned out without his input. My point is, and I'm sure your well aware that the nursery industry and the hospitality industry may not be what it is today for the abscense of the Tropical look afforded by the Coconut. I am not trying to be contrary, just pointing out the unseen impact on all our lives in this area. Just like the islanders in all the world I guess we'll have to hope the day never comes that the Coconut is put under the pressure of an epidemic. Maybe the only good that might come of that is the resultant LY resistant forms emerging from such trials.
And lastly. The Beccariophoenix is quite a charming palm that may put a few less lumps on tourist's heads over the next few generations.
Palmn, As I stated in my Post, the Town of Palm Beach has sucessfully managed LY through anti-biotics since LY hit and no less than 1,000 Jamaican Talls live quite healthily to date.Even specimens supposedly sensitive(Ie Prichardia's,Manillians,blah,blah and blah) to LY are currently unaffected. Many of these are not innoculated as far as I know. Perhaps the guard has been dropped and a only a new outbreak will invigorate vigilance.

One humorous story about LY fanaticism involves Worth Ave and the Palms that line this street for ladies interested in shopping.Worth had always used Manillians. When LY struck, the Town decided to decimate the Manillians even though they were uneffected. They planted Queens in their stead. That did not last long.(Idiots) They next moved to a relatively new Palm that was said to be resistant. It was the Woody. This was a great Palm that grew quickly but became far too massive with accompanying smudging from it's fruits. Worth is now back to Manillians and would have saved taxpayers $ if they allowed the originals to remain.

Other than antibiotics, I know of no other treatment. This is simply too costly for most regions. It would be great if we found that one of our new imports(say Nile Monitor Lizards) effectively controlled these insects responsible for the spread. I like the Window Pane but simply cannot agree that it will ever come close to the Coconut. Unfortunately, there are no replacements.
And I agree with you completetly that there is no substitute for the Coconut. I think the only reason any of us dare suggest such a thing is the liability and maintenance factor for some resorts. You and I can tell the difference pretty easily, but the tourist in from Frostbite Falls probably won't even blink at the difference. Given that logic, I wouldn't be surprised to see in our litigious times, some resorts around the world making the switch.
I can appreciate your Worth Avenue story. We have had a few genius' around here pull some serious landscape blunders in the gated communities to the tune of hundreds of thousands of dollars. Fortunately, it wasn't tax dollars.
Palmn, Maintenance and liability be damned. Give me my coconuts! I have watched as a kid in a Hurricane a coconut off an untrimmed tree hit a car like cannon ball. I am an attorney that does not chase ambulances but I know of no "coconut cases" here. I am not saying it could not happen but the cost of liability and maintenance is dwarfed by it's beauty. Look at the folks in California doing anything possible to grow the coconut(ie the Holy Grail).

Up in Vero do you see evidence of LY? It is a beautiful area that reminds me of PB 25 years ago. As you get close to the Ocean, I know I recall Coconuts,Royals and large Ficus/Banyans.It seems "tropical" enough to be effected by LY if it still remains prolific.
We have a large Coconut population here. They'll range to about five or six miles inland before they freeze to death. I was actually able to germinate a dozen or so Coconuts during the '07-'08 winter as it was so warm.
During the cold blasts of the eighties, we lost a lot of the old stately ones. Most of the ones out there now are maypan. We didn't have the LY here. Legend has it that the cut off line was Martin county. Perhaps it was because of the cold from '83-'89 that insulated this area from the vector insects, who knows.
On the subjust of pestulance, has the red palm mite been active in your area? There's been write ups of this as an impending issue in recent years.
Palmn, I have heared of the Red Mite but have not seen any effects from it here atleast at this time. The major pest is the "white fly" which eats the hedges of ficus if not sprayed. You see it from time to time but most spray.Hedges are big here.
This is a email I received from Monica Elliot at the University of Florida. They are collecting seedlings now to do testing on palms for disease. This is part of the email she sent us explaining the testing they are doing.

The disease I am conducting research on is Fusarium wilt (not TPPD), a fungal disease caused by a new pathogen Fusarium oxysporum f. sp. palmarum (proposed name). Information about this disease can be found at:


Information about this disease on the UF/IFAS websites will be updated after the scientific article we are about to submit is published.

While most of the diseased palms have been Syagrus romanzoffiana and Washingtonia robusta, we received two palms from the Kopsick palm arboretum in St. Petersburg that were claimed to be crosses (mule palms) of S. romanzoffiana x Butia capitata. We isolated the same pathogen from these two palms as we had from the queen and Mexican fan palms.

We have definitely shown that both S. romanzoffiana and W. robusta are hosts to this new pathogen, and have developed a seedling/young juvenile assay that we use to screen pathogen isolates and other palm species for susceptibility to this new pathogen. We would like to conduct an experiment that includes S. romanzoffiana (regular and ‘Silver Queen’), Butia capitata, W. robusta and mule palms to compare susceptibility of these different palm species to the new pathogen. We will be conducting the same test on seedlings of other Syagrus species, as seed (and hopefully seedlings) becomes available from the FLREC collection and that of the Montgomery Botanical Center in Miami
I think it's interesting that Ms. Elliot notes the Fusarium as new. Is it new to palms? Has it jumped the species barrier? I have been fighting fusarium in other plants for years, so I guess thats whats going on.?.
In her seedling assay's I wonder if the over use of nitrogen ferts. will be a consideration for their observations. One casual observation on my part is that nitrogen feeds the fusarium within the plant.
If she continues to communicate with you, please share her offerings.
I would also love to see whats been done with Ganoderma lately. It's been my observation that a lot of queens in our area have succumb to butt rot. This was dramatized by the recent spate of hurricanes, which culled out all of the infected queens. As a matter of fact a lot of palms that are good for Central Fla. are susceptible to Ganoderma.

Just what we don't need - more palm killers.

I haven't paid as much attention to these pathogens as I should. So, I may be off target a bit on the following:

The CIDP fusarium has been IDed as Fusarium oxysporum f. sp. canariensis. It is undoubtably closely related. I don't know what the "f" implies in both names. (If its just a repeat of the name "Fusarium, why is it a small "f"?) But I can only assume that given the difficulty we have in IDing and differentiating between Dypsis, telling similar Fusariums apart must be difficult as well.

I seem to remember a discussion about the decline of the supposedly bullet proof W. robusta in parts of SoCal. Does anyone else know of any reference to this? Or was I just dreaming it? If so, could it be the same pathogen.

SoCal without the "taken for granted" W. robusta would be like Florida without Cocos. It would sure highlight the cliché "you don't know what you've got 'til its gone."