Help with large Japanese Maple - Holes!!!

[foolin210]

Hi All,
I searched the site and couldn't find anything on holes in a japanese maple. Like others, I noticed a thinning in leaves and foliage and started to check the base, only to see a number of tiny holes throughout. Furthermore, pieces of the bark are coming off. Lastly, I noticed small little fungus fans (about 1/4 inch in width) forming on where the bark is splitting. See pics attached on all points.

I just had to take down an 80 foot red oak that had died due to ambrosia beetles in the backyard. Is that what this is? Can I stop them? I would be devastated if this tree died, as you can see it is really old and very beautiful.

Any help is greatly appreciated!!

 

[Ed Roland]

Hardwood borer. Variety of Ambrosia beetle is likely the culprit.

This could be the death of your tree without chemical treatment. Studies have shown a very high mortality once the insect has infested even with chemical barriers.

Call out a pro and ensure optimum cultural conditions.

 

[treeseer]

Call out a pro and ensure optimum cultural conditions.

the first of which is a healthy root system. Remove the mulch and soil from the stem and take a pictue of the roots.

 

[foolin210]

Will do, the roots "seem" pretty healthy (since I'm not an expert by any stretch). I'll post a pic tomorrow after the downpour blows through.

Thanks for the info!

 

[foolin210]

Here are some pics of the base and roots. As you can see, there are a couple overwraps on the front, which have been there for years. Other than that, all SEEMS good.

Again, all help is appreciated! I have an arborist coming out to give me a quote/assessment, but I'd like to take care of the problem myself, if possible.

Thanks all.

 

[Ed Roland]

Well, there's your problem. The tree is mighty stressed from having a portion of the trunk section in contact with moisture holding soil/mulch. The roots can withstand extended periods of moisture that will rot the trunk.

This is likely the primary stress that has allowed an opportunistic pest to take hold. Chemical barriers will help to discourage the borer issue but treatment MUST begin by removing the offending soil to expose the buttress flare.

The pro you have coming out should be ISA certified with a state pesticide applicators license. He/she will likely leave with a soil sample to determine ph and fertility. Expect a recommendation for chemical treatment and root collar excavation.

While you can perform the root X, with some research on proper technique, the insecticide should be applied by a licensed pro.

Do not fertilize this plant.

 

[foolin210]

Excellent, thanks for the advice!

 

[treeseer]

Remove the mulch and soil ***and circling roots***from the stem, and take a picture of the big roots growing away from the stem.

Go ahead, it won't hurt.

 

[Urban Forester]

The way that trunk/bark "corkscrews" into the ground I would suspect a girdling root. Beetles are drawn to "easy targets".

 

[Ed Roland]

The way that trunk/bark "corkscrews" into the ground I would suspect a girdling root. Beetles are drawn to "easy targets".

"But why should the tree spiral? More speculation here: Foliage tends to be thicker on the south side of the tree because of better sunlight. Prevailing winds, in most of the tree-growing northern hemisphere, are from the west. Combine these factors, and the westerly wind pushing on the thicker south side of the tree, year after year, causes an asymmetrical wind loading which slowly twists the tree around in the observed direction" Larry Gedney

It would be interesting knowing the tree site/orientation to said factors.

 

[treeseer]

"there are a couple overwraps on the front, which have been there for years."

You must remove these and find the first original, primary root. Your arborist should do this.

Well, there's your problem. The tree is mighty stressed from having a portion of the trunk section in contact with moisture holding soil/mulch.

Are you able to make this dagnosis without seeing the trunk flare?

I've seen jm stems covered with soil for a long time with no ill effects, where the roots are functional.

 

[Ed Roland]

The tree IS stressed from being buried too deep. Do you think not??

http://www.onlinegardener.com/care/Root collar disorders.pdf

A little something from our friends at the BTRL.

 

[treeseer]

The tree IS stressed from being buried too deep. Do you think not??

http://www.onlinegardener.com/care/Root collar disorders.pdf

A little something from our friends at the BTRL.

no doubt depth is a stressor, but imo sgr's are a more likely primary stressor.

Good info from the 1999 link, except this: Excavations
should not injure roots over 1/4” in
diameter. Adventitious roots over 1/4”
should not be removed from the trunk since
they may be providing substantial amounts
of water and nutrients to the tree."

SGR's were not recognized that much 9 years ago. Tom would not say that today. :censored:

 

[Ed Roland]

Tell ya what, Guy.

Lets split the difference. After root X it's very likely the homeowner will find girdling roots and, obviously, the tree is planted too deep.

The old tech article from Dr. Smiley was just to get a rise out of you since you have a problem with his choice of names for his patented procedure.

 

[S Mc]

Gentlemen, I have a couple of comments.

This appears to be a bug. Wouldn't it be a good idea to find out what kind of bug and then how it can be managed if at all? For instance, what I am reading about ambrosia beetles sounds pretty bad, however, I do not know if the articles I am finding are up-to-date. Have they come up with something effective? The initial reports are that if the plant is heavily infested then there is little or no hope.

The roots the homeowner showed in his photo cannot possibly be primary roots (IMHO) as they are WAY too small. Therefore, what Guy is suggesting to excavate until he FINDS primary roots is important. From the initial pictures it looks to me like this tree could be planted 2 ft too deep.

I know it is important to identify, if possible, all causes of stressors to trees in order to effect the best treatment plan. (And, if nothing else, learn by our mistakes.) However, if the primary issue is control of a pathogen then that should be done. Then remediation and control of the causal stressors can be addressed should you have a live patient to deal with.

Sylvia

 

[treeseer]

"Lets split the difference. After root X it's very likely the homeowner will find girdling roots and, obviously, the tree is planted too deep."

Agreed! And Tom and Bruce and the Bartlett gang have done a great job systematizing and promoting root invigoration. Some very good research at clemson on this lately--seen it?

remediation and control of the causal stressors can be addressed

Sylvia, you're right, but the whole tree has to assessed before treatment is prescribed. No Rx without an RCX!!