Parajubaea Torallyi problems

[Marc]

Hi everyone - My normally robust Parajubaea Torallyi is showing significant lack of color for the new leafs.  Any thoughts on whether it might be fungus, nutritional or watering issues?  I'm in northern california near San Jose.  We do not have high humidity, but we have had relative hot temperatures the last month or so.  The palm, seen here, is planted adjacent a lawn, so it should be getting enough water (the lawn is green and extends directly from the trunk to 20-30 feet from the trunk.  The soil appears dry on the other side of the palm.  I do have frequent gopher issues generally at my house, and have had large palms taken down before, but never anything even close to this size.  I've heard of die back issues for cocoides (I have a very healthy one 20 yards from the torallyi seen in the pictures here), but never for Torallyi.  The petioles still have some green on them, faint, but the leaflets of the new leaves are simply light in color (i.e., tan, not brown and not yellow).  I'd be grateful for any thoughts or recommendations.....  Marc

[Chris Chance]

I've heard they can just die for no apparent reason. Looks to me like the new growth is dead which is a bad sign. It could possibly be fungus in the growth point. 

[Hillizard]

Marc:  I took the advice of a forum member who recommended no water for this species all summer, which I followed. My P. tor-tor has to search for H20 if it wants some during our summers. I live in the Sacramento Valley, so we have quite a few triple-digit heat days compared to your location. Some of the blades on the south-facing fronds scorched, but otherwise this species deals with sun, heat and drought quite well. Below is mine from today (hand clippers for scale at the base).

[Marc]

Thanks - I'll try that, i.e., cutting off water and I'll also try applying some fungicides at the growth point.  This one is a bit of a puzzler, because the palm is big enough that there should be no fungal issues at the growth point, i.e., that doesn't get any moisture.  But I'll turn off the sprinklers and we'll see what happens.  I did examine the soil which appears very dry, but my palm is indeed fairly big and should be able to tap downward...

 

M 

[Jon T]

Marc, did your torallyi make it? Just saw this and immediately identified with your concern, since I have 8 medium-to-large parajubaeas -- and one healthy one just up and died years ago. It was pretty well-watered. As a result, I NEVER watered any parajubaeas after an initial few months of establishment watering even during the drought.

Jon T

 

[Marc]

Hi Jon - It's not looking good.  I have given it several rounds of fungal treatments and it has declined ever past the state seen in the photos above, though it still does have some green leaves.  I'm probably going to give it one more week to see if there is any new growth.  At this point, I have cut the straw colored leaves in the center back close to the growing point and have marked the cut line relative to the surrounding leaves with a sharpie.  My plan is to give it three weeks and see whether I see any sign of life, but at this point, it's not looking good.  However, looking on the bright side of it, if I do take it out, I plan on enlarging the planter it's in and putting three palms to better fill this area.  Any thoughts or words of wisdom on whether a palm that seems dead in the center might still recover?  My thinking is that if it goes 3 weeks with no sign of new growth, it's probably dead, but not an area I have alot of experience with.  The alternative of course would be to give it more time and assume that as long as there's any green even in the outer leaves there is still a chance.....

 

Best Regards,
Marc

[Jon T]

Marc,

I don't have any super suggestions, since it doesn't look like there's any obvious cause or cure. It's possible that you might have more likelihood of new growth if you leave it in place till mid-spring, since most palms are at least semi-dormant right now. Have to say that when my cocoid palms died from the spear, not in response to cold, the rest of the crown would soon turn gray and wilty, and then shrivelled. This happened with two butias, a jubaea, and one parajubaea over the course of several years. None recovered, unlike those with pulled spears from frost damage, which usually recovered well. Sounds like fungal or bacterial crown rot which often is fatal, but who knows -- you could try a drench of hydrogen peroxide.

Best wishes,

Jon

[Marc]

Thanks Jon - I appreciate it.  Yes, I'm on the fence in terms of pulling it out right now or waiting longer - I have tried H202 with no obvious effect.  However, it doesn't hurt to wait a few more weeks.....  Parajubaeas as far as I know buck the normal trend of winter dormancy (at least in CA) and I have heard stories of them throwing out 2-3 leaves in winter.  However, I see the logic in what you suggest, i.e., as long as there is some green, who knows? 

[Jon T]

Marc,

If you leave it in,  try to give it until mid-spring to see if it sends up a new spear after you cut the dead/dying spear down completely and soak the newly empty spot and the surrounding leaf bases with 2/3-strength peroxide. Since H2O2 kills such a broad array of earwigs, viruses, fungi, and bacteria, using it for a couple months might work a miracle. A mild not-too-wet winter might help, of course.

And sorry for 'splaining, if everything I've said is old news to you. The only credentials I have in this context are a history of doctoring a lot of palms, and saving a few.

Happy 2021! Peace and good health to you and your loved ones!

Jon

[Marc]

Hi everyone - No worries, and thanks for everyone's comments.  I did try several H202 soaks over the course of about 3-4 months, but finally caved in and cut it down - such a bummer, i.e., the trunk had about 24 inches diameter.  Weighing heavily on my decision, I cut down to closer to the growing point to facilitate treatment, and drew lines in sharpy trying to detect even the slightest amount of growth - Monitoring it in this way for approximately 10 weeks, I wasn't even able to identify the slightest, e.g., not even sub-millimeter change.  The normally tough fibers of the parajubaea were normal in strength near older growth, but abnormally weak in tensile strength closer to the growing point (e.g., they would easily pull out with a tug), and close to the growing point, even some leaves which preceded my issues were "rubbery" nearer the growing point  On inspecting the trunk after cutting it down, I found that the entire vertical center of the trunk was normal in color, but extremely and abnormally soft (to a point consistent with spear pull, i.e., extending at least five feet+ all the way down to the base of the trunk, i.e., even all the way to the root line).  There appeared to be no insect damage, but I believe based that the tree was already dead.  The roots also appeared normal color, but abnormally brittle.  Comparing the state of the palm prior to cutting it down verbally with the photo seen all the way at the top, within about 3 months of the photo at the top, all of the leaves had turned straw in color, except for perhaps just one that still had some green it in, and all the leaves had drooped close to ground.   I took out everything, including the primary roots.  Perhaps bucking fate, I put in another parajubaea close to (e.g., perhaps 2-3 feet way) from the old palm's location, and then put in a rhopalostylis perhaps 10 feet away on the other side. 

[Jon T]

A sad tale that most of us can identify with. You did your best. I think if we could train dogs to be rot sniffers, or build electronic sensors to detect (and destroy!) pathogens or pests, we would rarely suffer from the surprise demise of a recently flourishing tree.

I feel your pain. I'm going out now appreciate some of my "successes." And maybe sniff them and listen to their trunks.