Declining Sylvester Palms

[Drash]

Hello Forum Members,

In the early fall of 2025, I noticed that 1 of my 10 Sylvester palms was showing signs of decline. The lower fronds were dying. A spear had emerged but hadn’t opened up. I watched it for a few weeks after applying fertilizer and copper fungicide. I then reached out to a local arborist for advice on how to proceed. It was recommended to have the tree tested for Lethal Bronzing. I then submitted a sample for testing, and the results came back negative for Lethal Bronzing and Lethal Yellowing. I also had the arborist treat my other 9 palms with the antibiotic and insecticide injections as a preventative measure as I waited for the test results to come back. The arborist was thinking it was Lethal Bronzing.

Moving ahead a few months, The spear was still green, but hadn’t opened. Then I observed a 2nd tree that had begun to decline in the same manner. 

Any information would be greatly appreciated as to opinions on what could be wrong, and any suggestions to address the problem.

I’m hoping the test results I received were accurate. See attached photos of the 2 palms. My other 8 palms appear to be ok at this time. 

Regards,

Drash

 

[kinzyjr]

Welcome to PalmTalk.

It has the trademark symptoms of Lethal Bronzing.  If the arborist injects the affected palm with antibiotics and it the symptoms go into remission, it would all but confirm the test results were incorrect.

[Drash]

We didn’t inject the affected palm, which we should have done. We only did the other 9 trees.

[kinzyjr]

Hope that none of the others succumb to whatever it is.  My own thoughts are Lethal Bronzing.  We've lost thousands of Phoenix species.  The typical choice for replacement is Livistona decora locally.  Out of all of the Phoenix species, the Phoenix reclinata hybrids in the area seem to have the least issues, followed closely by Phoenix roebelenii.  All of my Phoenix have started to flower at the same time, so who knows what kinds of mutts will be produced.

[Drash]

Thanks very much for the replies.

I will proceed with removing the 2 trees.

From what I’ve gathered from different sources, I also think it’s Lethal Bronzing.