Advice sought on serious fungal issue with Jubaea in Vancouver BC

[bostock]

I am gutted. A 15 yr old jubaea in ground for 8 yrs is seriously ill with what I believe is a fungal infection.

Quick background. We have suffered through 2 back-to-back winters with -13.5C minima. First winter (2021/22) I covered with tarp and rope lights over cold period and palm emerged in good form; no problems. Second winter (2022/23) I did the same thing but I was not in a position to remove the tarp for 2 weeks following cold snap as I was out of town and didn't realize it would be a problem (I protected a large chamaerops the same way; it had no issues). During that time jubaea developed a fungal infection that affected many of the outer leaves. I was hoping the palm would grow out of it but now that warmer weather has arrived, the infection seems to have spread all the way into the growing bud. The palm has attempted to push out some small fronds that start out greenish but then die. I am worried that palm will expire unless I do something.  I am hoping someone on this board might have prior experience - should I use sulfur or bordeaux powders? hydrogen peroxide (if so what concentration)?  Advice based on experience would be very much appreciated!!

Michael in Vancouver

[swolf]

When you give a gentle tug on the center spear, does it hold firm?  If instead the rotted leaves pull out, then the usual advice is to pour hydrogen peroxide (standard supermarket concentration) down the crown cavity.  A systemic fungicide soil drench is something I would immediately do either way.  I believe the brand name combo I have used in the past was “Banrot” along with “Subdue Maxx” since they complement each other.

Steve

 

[Las Palmas Norte]

21 hours ago, bostock said:

...The palm has attempted to push out some small fronds that start out greenish but then die. ...

I have a Trachycarpus that's doing exactly the same thing. Lately there's been no new emergence of new fronds but the spears won't pull either. I think that Jubaea at that stage of early development is really a zone 9 palm. Once the palm becomes sizeable and more developed, they achieve their true hardiness levels. Let's hope for a full recovery.

[Chester B]

3 hours ago, swolf said:

When you give a gentle tug on the center spear, does it hold firm?  If instead the rotted leaves pull out, then the usual advice is to pour hydrogen peroxide (standard supermarket concentration) down the crown cavity.  A systemic fungicide soil drench is something I would immediately do either way.  I believe the brand name combo I have used in the past was “Banrot” along with “Subdue Maxx” since they complement each other.

Steve

 

If you can't get the soil drench one, you can try a standard copper fungicide that you spray.  Spray the whole palm especially in the spear, and keep the palm dry.  cover it with something temporarily when it rains, at least the spear.  

To be honest it's not looking very promising, but I would keep checking that spear.  Just because it isn't pulling today doesn't mean it won't in a couple of weeks.  The fact that the older fronds are dying from the bottom up and the spear is going crispy there is a good chance its dead,  I had a Butia do the exact same thing this spring.  It first started with the older fronds, the spear crisped up.  2 or 3 weeks later the entire spear and surrounding fronds all pulled out leaving a giant hole almost to ground level.  

Good luck and I hope it turns out well for you,  Jubaea are pretty tough.

[SeanK]

Fortunately, most of summer is ahead of you. Jubaea's native landscape has a climate more similar to San Antonio, TX. Z9 but dry.

[bostock]

Many thanks for your thoughts - I have thoroughly sprayed the remaining leaves and spear with bordeaux mixture, and will leave it now to its own devices...

[tarnado]

What ended up happening? Success? Doom and gloom? I really hope for a happy ending for you all!