Trident maple health


Hello Jonas,
I have a Trident Maple has not grown well since I purchased it in 11/2011. Leaves are stunted when they come out in spring and turn brown to black on the edges. Branches do not extend. I repotted this past spring, roots look normal and still have the same results. I took some leaf samples to the AG department and they found no pathogens in the samples that could be causing this problem. I have other Tridents with no problems. Anyone else have this problem or have a cure?


(Jonas Dupuich) #2

Sorry to hear it. I’ve had similar problems with trident maple and have started to see this in other gardens too. Did the ag folks run plates or just guess based on appearance? I’ve guessed that fungus is the problem and that regular spraying would be required - in winter when the tree is dormant and then throughout the growing season - to keep the tree healthy.

I’m planning to use a big pot when I repot this winter to give the tree room to grow and up the level of spraying next year to see if that helps.

Will be curious to hear if others have suggestions.

(John) #3

I’m not an expert to say. I only have 1 trident and only had if for one season, but heard that they grow like weeds. I’m in Maryland and have mine in plan turface. Could it be soil ?


Ag tech ran plates and they determined that it may be fertilizer burn. They recommended using fertilizer sparingly. I hadn’t used fertilizer yet prior to bringing in the samples. When I repotted this past spring I used clay king mix to make sure it wasn’t my soil mix. Still the same results.
Any recommendation on fungicides?

(Jonas Dupuich) #5

This is interesting. The Ag folks I visited suggested something similar - salt burn - even though I hadn’t been feeding or treating the tree with anything at the time. They thought it might be the water, but I had my water checked and the salt levels are very low. I have other tridents growing inches away from the affected tree and they are really healthy - growing like weeds as they have been for years. I’ve also tried a couple of different kinds of soil and have seen no difference between them.

I can’t recommend specific fungicides without knowing which pathogen - of if there’s a pathogen - that’s affecting the tree.


I have tried systemic and copper based fungicides from a local nursery and still no good results. This year has been the worst for this tree and seems to be declining more each year. I’m thinking about putting it in the ground as a last resort. What do you think.?

(Jonas Dupuich) #7

Sounds good to me, depending on how cold it gets where you live (I wouldn’t want the tree to freeze solid during winter). Either planting it in the ground or in a large container that you set on the ground will better insulate the roots and give the tree a chance to regain vigor


Thanks for your help. I’m in the east bay, weather should not be an issue. I’ll up date in spring on the result.

(Jonas Dupuich) #9

Sounds good - I’ll be sure to provide an update if I learn anything as well.

(Dylan Ferreira) #10

I am thinking Xylela fastidiosa or fluorides in the potting mix.

(eric) #11

I have at least one tree that is also infected, perhaps two or three others just getting it too. From the way it’s acting it seems clear that it is a fungus or virus problem, something infecting the plant.

It’s possible that the infection is not in the leaves, rather it is in the vascular system. Hypothesizing that the shutdown of parts of the metabolic pathway are mimicking salt burn.

@bonsaitonight - weren’t you going to try sending a branch to the lab rather than just leaves to see if it got different results?

For what it’s worth - it appears that the type of Bayer systemic that also includes a systemic fungicide has at least slowed down the spread of the disease. I’ll be testing this further in the spring.


After reading your comment I went back to Dylan’s and started researching about Xylem Fastidiosa. This disease has all the symptoms of this Trident. I will be bringing a branch sample to the Ag department for testing and will post the results when I receive it.

(Jonas Dupuich) #13

FYI - I took my tree to the UC Davis Plant Disease Clinic today and talked with them a bit. I left branches and roots so they can run tests. No big clues today, but they will check for xylella. Will provide an update when I hear back from them.

One thing they did notice was that the black spots on the leaves were signs of fungus, a normal occurrence as the leaves were dead or dying and simply breaking down.

(eric) #14

I was just doing some reading on this. Here are significant items to consider and that match the problem:

Xylela fastidiosa:

  • infects a broad range of plant material including maple species.
  • Spread by insects that suck on sap of plants, like leaf hoppers etc. The bacteria is present in the gut of the insect once infected so it can infect many plants.
  • The disease is not spread by proximity, or contact as it resides in the xylem, not on the leaf surface.
  • Stress is a factor in showing symptoms, but lack of stress (e.g. ground growing) will not cure the plant, but only allow it to grow despite the infection.

I would surmise that It is very likely that bonsai culture, particularly cutting of infected tissue and then cutting of an uninfected plant, would spread the bacteria.

Of particular interest is the following:
“No cultivable X. fastidiosa was recovered from any of the media, buffers or
xylem sap after 24 hours at -10˚C” (From )

I found reference to A. buergeranum being hardy to USDA zone 4a, with low temperatures of approximately -30˚C. Therefore, I am considering a mid-winter dunk into a freezer for an infected trident to see if it cures the tree.

@Dylan_Ferreira : It seems optimistic to rely on fungicides, particularly since this appears to be a bacterial problem. Do you know of a xylem bacterial treatment? If we can take penicillin, there should be some way to get a plant to uptake an anti-bacterial agent, right?

John Kirby recommended that I try ZeroTol or Cleary 3336. Unfortunately, I’ve only been able to find them in very large packages…2.5 gallons of ZeroTol for $150

Also of note regarding this problem: I have 2 cotoneasters that may be exhibiting symptoms.

(eric) #15

Some further reading with another possible treatment using Abscisic acid (ABA), reference at bottom:

“10 ppm VBC-30030, the more active and stable ABA drench
treatment…resulted in 100% curing in Pinot Noir and 81%
curing in Cabernet Sauvignon.”

"When the grapevines were going dormant
but still had attached leaves in early November of each experimental
year (2005, 2006, and 2007), foliar sprays or soil drenches of
ABA solutions were applied to healthy and X. fastidiosa-infected
Cabernet Sauvignon, Pinot Noir, and Chardonnay (2007–08 only)
vines. Two ABA compounds were provided by Valent Biosciences
Corporation. One was a naturally occurring ABA (VBC-30054)
that has a comparatively short persistence time (12 to 24 h) and is
UV sensitive. The synthetic ABA (VBC-30030) has a greater persistence
time of 24 to 36 h and was less light sensitive. Each ABA
powder was dissolved in 99% ethanol to generate a 100,000 ppm
stock solution. ABA stock solutions were diluted to the desired
concentration using deionized water. "

Based on the cold study, the authors of this paper surmised that the plants were producing ABA in reaction to the cold temperatures, which was at least partially responsibly for the curing seen in the cold-treated plants.

Note that treatment has to happen in early to mid-November if the results of this paper are to be duplicated.

(eric) #16

In reply to a query to Melody Meyer (author of papers mentioned above) at UCD I received the following:

On the cold curing front, the relationship between cold temperatures, the host and the bacteria are critical for effective cold curing. Since we did not test maple, I am not sure how effective cold curing would be. Also, Bacterial Leaf Scorch (BLS) on maple is mainly found on the east coast where the temperatures sometimes drop below the -5 C to -10 C range, and they still see infections that survive the winter.

As part of my research, I put potted grapevines in walk in coolers set at various temperatures. The ones subjected to the -5C treatment, had the most curing, but in some years, had the highest mortality rate. I think this high mortality rate was due to the dry conditions within the cooler. If you do attempt to “cold cure” your trees, I think it is important to keep the plant hydrated, and in soil.

Cold curing in maple is not a sure thing or without risk. I would recommend getting a lab confirmation and then consider cold therapy. Here are two extension articles on the topic. I hope this is helpful.

I didn’t find the first extension article to be particularly insightful since it erroneously mentions that the disease is uncurable (when the cited papers mention curing in grape vines.) The second one is a bit more interesting thought.


I recently got the results from the Ag department on the root and branch samples. No pathogens found in the branch samples but found a root disease called Cylindrocarpon Disease ( Black Foot Disease) . This disease have been found in grape vines. I talked to Lab Tec. at UC Davis and they recommended to use Topsin M or a fungicide containing Thiophanate Methyl. Cleary 3336 is one that has this chemical in it. Both comes only in large quantities, more than I can ever use. Anyone have a lead on smaller quantities?

(Dan J) #18

Did you rid your trident of black foot disease? My trident seems to have the same symptoms.

(Jonas Dupuich) #19

Good question. The trident maples look good as of today, but the symptoms tend to get worse as the season progresses. I’ve been treating them with gypsum, which can be used to address salts in the water. I sprinkle some on the surface of the soil about once a month.