Dying palm? Please help!

[VicG]

Hi- last night the 3rd trunk of my palm fell over- the inside was black. What is the matter with the palm- i have looked and looked and cant find exactly what fits this description. I have included pics of the black spot where it once stood. 
 

Thank you!

[Jim in Los Altos]

Not sure what caused its failure but the good thing is that you had three completely separate Phoenix roebelenii palms. It’s not a single plant. Now you have two so whatever happened to the one palm won’t necessarily affect the remaining two.  

Edited January 2, 2022 by Jim in Los Altos

[Johnny Palmseed]

@VicG Welcome to the forum. It seems that it rotted out which is somewhat unusual for a Phoenix Roebelenii as it generally prefers wetter conditions. It looks like you have a sprinkler emitter right on the plant. How often do you water?

[oasis371]

We also have no idea where the OP is located. 

[VicG]

Hello! 
Thanks for the responses- we live in Phoenix, the palm is located in my backyard . It was planted last year and i notices that one struggling this past summer. All of a sudden it just quit growing.  The drippers are off right now- lots of rain lately. But I dont think i overwater usually. 
If you look where i circled in yellow there is the black rotted remnants of the trunk. I did see tiny bugs in there- not sure what to think though as far as how much of the cause they were. 

[VicG]

9 hours ago, Johnny Palmseed said:

@VicG Welcome to the forum. It seems that it rotted out which is somewhat unusual for a Phoenix Roebelenii as it generally prefers wetter conditions. It looks like you have a sprinkler emitter right on the plant. How often do you water?

Not too often- drippers are off currently bc of rain lately

[Johnny Palmseed]

It’s good that you posted your location as there are people in your area who are better suited to answer your questions. If you just planted it last year, it probably already had the problem but it didn’t show itself until now. Unfortunately with multiple plantings, it is somewhat common for one or more palms to grow at a lesser rate than the others or even die off. Your triple is now a double and it could continue as such or it might eventually become a single. Usually the palms will continue to grow but the orientation might seem off now. 

[Jimhardy]

Was the "dripper" on at one point because it does look like

it could have been soaking the trunk there and possibly some rot 

started and the moisture and heat(feeding the rot) were just to much for the palm to overcome.

[Merlyn]

I'd suggest changing the irrigation from the 360 degree stream sprayer to a plain button dripper or a couple of small fans.  The general idea is to wet the roots and NOT hit the trunks.  The position of that 360 degree sprayer is hitting all the trunks.  My guess is that the rot was caused by the sprayer.

I'm not sure how much water those palms need in Phoenix, probably a lot more than where I live in swampy Florida.  But you could do something like 4x 1 gallon/hour button drippers, and run individual 1/4" lines to 4 spots within a 3' diameter of the trunks...but not within 6" of the trunks.  OR you could put a pair of 90 or 180 degree fans near the trunks but pointing AWAY from the trunks.  That way you'd spray the ground near the trunks but not directly on them. 

[VicG]

Thank you!! I will definitely focus more on the water as an issue- it is just unbearably hot here in the summer and the palms take a beating- still trying to get the right amount of water- not sure how that one got so rotted but I suppose anything is possible