Hello,

New to this message board but have seen some great posts already. I have an issue that I'm desperate to solve:

I planted a young tamukeyama Japanese Maple in my garden 3 years ago, located in Pittsburgh PA. I have fertilized, staked and watered to the best of my knowledge and have watched it grow over the years. It is certainly my prized possession in our small garden, and sadly it appears a small white pest - Mealy bug (from what I can tell based on pictures) - has infected the trunk and limbs.

I never had any issues in years past, as the tree has been healthy and growing, but this week I realized that only the bottom few branches were getting new leaves. The upper branches (majority of the tree) were dead and snap off easily.

There were only a few visible mealy bugs when I noticed the damaged trunk, which I killed/removed and sprayed the trunk with an insecticidal soap. However, I'm wondering what my next move should be: Will the tree ever rebound? Do I need to cut it back? If so; then how? In a worst case scenario, can I salvage the healthy parts of the tree and re-root/plant?

I love gardening but this is all fairly new to me, but I love this tree and hope that someone can offer some guidance. I have several photos but it appears I can only upload one - let me know if I can post the rest.

Thanks in advance.

Mealybugs did not destroy your tree - they don't chew on trees, just suck fluids. Photo #1 is a little too close and I can't really see it in your other photos but I suspect that's the graft. Your JM was top-grafted and part of the graft has failed. There's nothing you can do to revive the dead part but, with some effort, you can save and train what's left - it would be a multi-year effort. I had one break leaving only one branch. With patience and pruning, it turned into a nice tree but it took 15 years.

PS: You can start them from cuttings but its not easy - I haven't tried it. Any cutting calling for IBA over 8,000 ppm means its a difficult to root, woody plant.

From Hartmann & Kester's Plant Propagation: Tips of vigorous pencil-sized shoots in late spring, placed under mist with bottom heat in a greenhouse, treated with IBA 8,000 - 20,000 ppm. Wait until the terminal bud has formed but before the last set of leaves has fully expanded.

I appreciate your replies. I had another person tell me it could be root encirclement, but my question in regards to this possibility was "why would only the upper branches die, and not the bottom"? Your idea of the graft failing is interesting and sounds very possible. It sounds like there isn't much to do if that's the case. Which branches would I was to cut - all dead branches above the healthy ones? Or is there another suggestion on how to trim/tidy what's left of the tree...

Thank you!

Lucy68 said: Mealybugs did not destroy your tree - they don't chew on trees, just suck fluids. Photo #1 is a little too close and I can't really see it in your other photos but I suspect that's the graft. Your JM was top-grafted and part of the graft has failed. There's nothing you can do to revive the dead part but, with some effort, you can save and train what's left - it would be a multi-year effort. I had one break leaving only one branch. With patience and pruning, it turned into a nice tree but it took 15 years.

Branches that snap ate dead. Branches that bend are not. If you aren't sure, scratch the brand. Dead/dying branches are hard or brown just below the surface. Live Branches are green.

After looking up growing JMs from cuttings, I'm thinking about trying just because. Lots of JMs around my house. I even have the right IBA and a greenhouse.

Finally got a chance to uncover the roots - and this is what I found. A bit strange, no? I'm not sure if this is a sign of root encirclement or something bad; but any insight is appreciated!

Roots growing in a circle just means, for some reason, the roots didn't leave the original planting hole. That isn't necessarily a problem unless the roots strangle the collar flare (where the trunk and roots join) and choke off nutrients and water. You uncovered the collar flare and I can't see any strangling roots.

Hi, did you untangle or made 2-3 deep knife cuts to the root ball before planting? If you didn't you might have too many roots growing inwards or circling the original root ball. That eventually will prevent water from getting in and the plant will slowly dry out over the years. That might be what is going on here. It happened to me once a few years ago with one Bloodwood.

I quoted myself by mistake, sorry 😔 I was just trying to correct some grammar errors on my original answer.

Lucy68 said: Roots growing in a circle just means, for some reason, the roots didn't leave the original planting hole. That isn't necessarily a problem unless the roots strangle the collar flare (where the trunk and roots join) and choke off nutrients and water. You uncovered the collar flare and I can't see any strangling roots.

Hi Lucy68, sorry, but I beg to differ: circling roots or never leaving the original planting hole are big problems even if there is no strangling (girdling) of the trunk. The roots must go in all directions to seek water and nutrients. If that doesn't happen the tree will never establish and it will die in the first harsh winter. Also too many roots growing inwards or circling will pack the root ball to a point when it will become hydrophobic and then no matter how much you water the plant will dry out. Just my 2 cents.

You can disagree, I don't mind at all. But how do JMs stay happy in pots?

Go back to photo #1. What are we looking at? I don't think the tree is dying because of congested roots - I suspect the graft is not healthy. Its top grafted, probably with more than one bud.