Any chance we can save our Canary Island Date Palm from South American Palm Weevil?

[Chubbspeterson]

I found a South American Palm Weevil under my CIDP and upon looking more closely from an elevated spot, I noticed the top was quite flat. I called a tree care company and they said that the palm is likely too far gone and that it can't be saved. There is a smaller CIDP next to it that looks healthy, so our plan is to treat both with insecticide as a preventative measure to save the smaller one and kill whatever is in the big one.

I'm not really sure how long ago the palm was attacked, but I'd guess sometime this summer. The last photo I have of it looking healthy is the "post trim" photo taken in Feb 2024, although we had them trimmed in Aug 2023.

Below are some photos showing different time periods.

We are absolutely crushed at the thought of having to cut down this palm. It was planted in the late 80s and is a real statement piece in our backyard.

Are there any other measures we can take other than flooding the crown with insecticide? Is there any chance this palm comes back after treatment or do we have to cut it down?

 

PRE TRIM SOMETIME IN EARLY 2023

 

DAY OF TRIMMING AUGUST 2023

 

POST TRIM FEB 2024

 

CURRENT STATE NOV 2024

[TropicsEnjoyer]

I’ve thankfully never had to deal with this disgraceful pest but unfortunately it seems your tree is on the verge of death if not already doomed. Hope you get some other input soon but I would try to take a look at the crown and see if there’s any growth remaining, if you can somehow find a way to get up there.

[Merlyn]

@Chubbspeterson it's hard to guess when the SAPW attacked it, the February 2024 photo looks pretty good.  Unfortunately I'd agree with your tree care company.  If the crown is collapsed that far it's probably mush inside and the growing point is dead.  I'd definitely do a crown drench of insecticide on the other CIDP, and follow up asap with a soil drench of Imadicloprid.  There's a good chance it's been attacked too, but just doesn't have any visible symptoms yet.

[SeanK]

Chainsaw the first and Drench the second. Sorry for your loss. They were both beautiful 6 months ago. 😢

[DoomsDave]

@Chubbspeterson NICE TO MEET YOU!

So sorry for the reason.

Sadly, I must completely concur with @SeanK's brutally succinct advice.

Alas.

[talkjk]

23 hours ago, DoomsDave said:

@Chubbspeterson NICE TO MEET YOU!

So sorry for the reason.

Sadly, I must completely concur with @SeanK's brutally succinct advice.

Alas.

Is chopping it done quickly the right thing to do? Or should you use it as bait and kill as many of the little bast....s as you can? If the tree is still living could you drench the crown and soak the roots with Imidacloprid thus becoming a booby trap. Or would it be too risky attracting a bunch of reprobate and take down the rest of the neighborhood? 

[DoomsDave]

1 hour ago, talkjk said:

Is chopping it done quickly the right thing to do? Or should you use it as bait and kill as many of the little bast....s as you can? If the tree is still living could you drench the crown and soak the roots with Imidacloprid thus becoming a booby trap. Or would it be too risky attracting a bunch of reprobate and take down the rest of the neighborhood? 

Good question! Maybe hit it with some i-juice and wait, but not too long. Then burn it up.

Unless and until a natural enemy to keep those things under control can be found, we're going to have a disaster, at least for CIDPs just like in the Mediterranean region.

[SeanK]

52 minutes ago, DoomsDave said:

Good question! Maybe hit it with some i-juice and wait, but not too long. Then burn it up.

Unless and until a natural enemy to keep those things under control can be found, we're going to have a disaster, at least for CIDPs just like in the Mediterranean region.

Hmm. If it were mine, it would be gone this weekend.

[maxum2610]

In my opinion this palm can be saved. A few years back I had one in far worse condition than this one in my house in Moraira Spain. The grow point was fully inclined to one side. What we did was to remove all the leaves as close to the stem as possible. Then we had them spray from the top, profusely every two weeks three or four times. The palm took a long time to recover but looks fine now. Finally I had them inject the trunc about 1.5 meters from the top. This is something that is done here a lot in Spain in the Valencia region, and in my opinion, the only thing that can save your palms long term. There’s an excellent brochure online from the Valentine community on how to take care of your canary date palms. Also, you may want to look into getting palm weevil pheromone traps. They work great in reducing the population in your back yard, and keeping them away from your palms. Don’t wait to spray the palms. Do it asap. Once the larva’s get into the grow point, it’s done.

 

[maxum2610]

Also, I noticed you had your palm trimmed in August. Never have it trimmed in a period that the rpw is active. If you must trim it, do it in January or February. Trimming your palms attracts the rpw, so if you must trim it, do it in the months that they are not active. 

[Mark in Portugal]

I saved a tree that was in a similar state; but it was close, and I really thought it was done for.

I had treated the tree before any symptoms appeared (I was dosing every 3 months). After the top leaves fell away, there was some new growth and I thought it would be ok; but the new spear leaves fell over and I could pull them out with a light tug. The heart was rotten.

 

So I cut my way in through the side, and cleared out all the rot and dead insects. A couple of months later, new tiny leaves emerged.

Today the tree is huge and in great shape again. 

 

 first sign of infection, Feb 2015

 

July 2016 with new leaves

September, 2016

 

November, 2017

 

[Patrick]

On 11/9/2024 at 10:08 AM, DoomsDave said:

Good question! Maybe hit it with some i-juice and wait, but not too long. Then burn it up.

Unless and until a natural enemy to keep those things under control can be found, we're going to have a disaster, at least for CIDPs just like in the Mediterranean region.

I've noticed some suspicious phoenix palms up here in northern california. What is the cold tolerance of these bastards? 

 

I remember they were quarantining a few years ago in certain so-cal areas but I lost touch of the end results of those ventures. That was several years ago and covered here on PT. I have not thought much about it until now, and these collapsed CDIPs that I saw here in town....

[Mark in Portugal]

They withstand a moderate frost at least.

I treat my canary date palms with pesticide every 6 weeks, and that has been working for about 10 years. 

At first I had a silly notion that the problem would get solved somehow, but now I think it's an endless battle; whenever I stop treatment, all our canary date palms will get weevils and then die. 

So actually, it's probably a better idea to tear them out and plant non-susceptible species.

OH won't have that, so it's pesticide city here. 

[Tracy]

10 hours ago, Mark in Portugal said:

They withstand a moderate frost at least.

I treat my canary date palms with pesticide every 6 weeks, and that has been working for about 10 years. 

At first I had a silly notion that the problem would get solved somehow, but now I think it's an endless battle; whenever I stop treatment, all our canary date palms will get weevils and then die. 

So actually, it's probably a better idea to tear them out and plant non-susceptible species.

OH won't have that, so it's pesticide city here. 

I have to point out that Europe has a different species of weevil than we are dealing with right now in California.  Although similar in their dietary preferences, there may be some differences in other ways.   Both species can be treated preventatively with neonicotinoid drenches but I wouldn't immediately assume their cold tolerances ard identical.   

Another question would be whether the larva can survive cold inside a living palm only to have them emerge when temperatures increase?  

The preferred treatment here was Imidacloprid but neonicotinoids were banned in California January 1 of this year.  I posted the same question about alternate treatments in another post after finding one on my prized Ravenea julietiae.   Anything else being used on any of the palm weevils?

[Tomas]

17 hours ago, Tracy said:

Another question would be whether the larva can survive cold inside a living palm only to have them emerge when temperatures increase?  

The fermenting inside the crown will provide heat, so the larvae can survive in quite cold climates

[Tracy]

On 2/15/2025 at 3:37 PM, Patrick said:

I've noticed some suspicious phoenix palms up here in northern california. What is the cold tolerance of these bastards? 

 

I remember they were quarantining a few years ago in certain so-cal areas but I lost touch of the end results of those ventures. That was several years ago and covered here on PT. I have not thought much about it until now, and these collapsed CDIPs that I saw here in town....

You recall accurately.  There was an infestation in Southern California that was contained about a decade ago:  https://cisr.ucr.edu/invasive-species/red-palm-weevil

As you can see that was the red palm weevil, Rhynchophorus ferrugineus. We are currently fighting the South American palm weevil, which is  Rhynchophorus palmarum.  As I mentioned above, I don't think that our friends in Europe have had to deal with the  Rhynchophorus palmarum, not to belittle their fight at all.  While there may be a lot of overlap in their behavior,  I don't know that we can automatically assume that things like cold tolerance will be identical for both.  I would be worried if I were seeing CIDP's in your area dropping as well.  There is always the possibility that the weevil could hitch a ride on a nursery shipment from the southland and skip over other areas between San Diego and the northern portions of the Central Valley.

 

[Mark in Portugal]

Yes, we have the red one; imidacloprid is banned here now too (with a couple of exceptions). Other pesticides work too, but don't remain in the plant for long.

I just pour the mix into the low trees with a dipper, and was using a dosing pump to dose the high trees. That's really slow (hours), and as I now have 8 tall trees I made a new system, a hand pump with a 3m (10') long tube I can push between the upper fronds. 

I took this picture at home.

[Phoenikakias]

20 hours ago, Tracy said:

You recall accurately.  There was an infestation in Southern California that was contained about a decade ago:  https://cisr.ucr.edu/invasive-species/red-palm-weevil

As you can see that was the red palm weevil, Rhynchophorus ferrugineus. We are currently fighting the South American palm weevil, which is  Rhynchophorus palmarum.  As I mentioned above, I don't think that our friends in Europe have had to deal with the  Rhynchophorus palmarum, not to belittle their fight at all.  While there may be a lot of overlap in their behavior,  I don't know that we can automatically assume that things like cold tolerance will be identical for both.  I would be worried if I were seeing CIDP's in your area dropping as well.  There is always the possibility that the weevil could hitch a ride on a nursery shipment from the southland and skip over other areas between San Diego and the northern portions of the Central Valley.

 

If you have missed following information, rpw has a tropical origin too but from the palaeotropics (i.e. southeastern Asia) and initially had been imported with dactylifera offshoots (at least this is the official story) from Indonesia to Arabian peninsula and from there to Middle East and Egypt and from there to Spain through import of tall CIDPs (allways this is the official narration in an international Congress on this pest). Provided this information is true, the rpw turned out quite versatile and adaptable. Call me an illusioner if you like, but I think rpw' s activity is slowed down by increased air moisture and/or shade and gets conversely crazy with intense sun and high temp seeking quickly a in latter case a comfortable shelter inside the leaf axils of palms.  I have observed several times couples of conspecific palms growing ivory closely but one being fully exposed to sun and the other being under some canopy of a larger tree. Always the palm to be attacked was the fully exposed one! Not that sapw as a different spp could not have a different biology, but this possibility would not make me more optimistic.

[Patrick]

On 2/17/2025 at 9:25 AM, Tracy said:

You recall accurately.  There was an infestation in Southern California that was contained about a decade ago:  https://cisr.ucr.edu/invasive-species/red-palm-weevil

As you can see that was the red palm weevil, Rhynchophorus ferrugineus. We are currently fighting the South American palm weevil, which is  Rhynchophorus palmarum.  As I mentioned above, I don't think that our friends in Europe have had to deal with the  Rhynchophorus palmarum, not to belittle their fight at all.  While there may be a lot of overlap in their behavior,  I don't know that we can automatically assume that things like cold tolerance will be identical for both.  I would be worried if I were seeing CIDP's in your area dropping as well.  There is always the possibility that the weevil could hitch a ride on a nursery shipment from the southland and skip over other areas between San Diego and the northern portions of the Central Valley.

 

I'm gonna say Moon Valley is the vector, Victor.

 

99.999% not true, but the big nurseries with all these regional locations could easily move a critter from here to there. That goes for the big box stores, too. 

 

Thank you for the refresher. I did not realize it was a new species giving us trouble, currently.