hey

i dont know how you jump to root rot ...

looks like what happens in the great white north with a hard frost or freeze after buds begin ... most likely that is ruled out for you ... lol ... one usually ends up simply pruning out the dead stuff ...

look at the different trunk color ... you can almost tell which parts are out of ordinary ... and probably dead ...

whats all the white stuff in the soil???

whats you soil type .. ???

deep shade is not really the best for any tree ...

the hole under the trunk bothers me ... why would your hill collapse.. how did you plant it???

good luck

ken

The soil is quite sandy I would say. The white stuff is gravel. The root crown has been always kept clean from any debris.

I planted it on man made hill which I created from a soil collected from adjacent areas. I planted it with standard procedure creating one and half larger hole where I placed the tree after removing the cloth around the root ball.

I don't think the hill is collapsing. I think it's just some of the soil crumbled right under the tree crown and created a hole. But I am gonna give it a closer look ti see if it's not a rodent issue.

I would think that bloodgood would take shade like that. It' not necessarily deep shade. It just never gets sun because it's against a north side of building on the other side of the fence.

I expect tiny little mounds to have perched water tables if the mound wasn't incorporated into native. That would help weaken the tree. This winter's weather is another factor. Another is the shade. Another is the proclivity of this tree to have dieback every winter.

Dan

as with any description of shade.. all i have to go on.. is that you said it was 'deep shade' ..

whats the deal with the wall behind it ... anyone been working back there.. seems kinda coincidental that it has died from basically the fence up ... any suggestion that the neighbor is somehow involved???

i am just trying to wiggle some more facts out of you ... as i said.. up here in my z5 MI ... that kind of die back happens all the time ... depending on a micro climate ...

now.. does that 10 next to your name mean you are zone 10 .. cursory review of google says JM's are z5 to 9 ... are you zone pushing .. are JM's prevalent in your area??? .. could you even be pushing a higher zone ... [and if it is that sunset stuff.. thats greek to me.. lol]

anything out of the ordinary this winter.. or what you call winter in SF ... lol ...

where's bboy???

ken

If there's a collapsed pocket, I'd try to fill it.

Good looking ferns, though...Western Sword and Giant Chainfern, yes?
Two of my favorites.

Josh

greenman28
I have filled the collapsed pocket already. Yes, you got those two ferns right. Western Sword gets little "burned" like look but I am looking at the "perfect" garden look.

ken_adrian
there was quite a lot of rain this winter as I mentioned and also there was once very cold night when we were expecting snow. snow didn't happen but i think it was very close to freezing point. i can't confirm that though. there is no construction at the fence. that fence just looks "unfinished"

dan
i didn't quite understand: "tiny little mounds to have perched water tables". Does it mean that water table actually rose into the mound and the roots are rotting?

I am not sure what to do at this point but I guess I'll prune dead wood, inspect the flare again for rodents and WAIT...

Does it mean that water table actually rose into the mound and the roots are rotting?

It means the interface of mound and native is continually saturated and will not drain until the entire soil column is saturated; this depletes the roots of oxygen and gas exchange from below.

Dan

Hey, Martin, my Sword ferns have the same look....
thankfully, the new fronds are unfurling now to replace the old.

Josh

Japanese maples are prone to various soil fungal pathogens, Verticillium wilt being the star performer :-) Typically this will manifest in dieback of entire sections of the tree, much like your photos indicate. I'd suggest confirming a diagnosis by taking a sample of your tree into your local extension office or a well-qualified nursery/garden center. If confirmed, the outlook is not good.

VW is an opportunistic pathogen that is present in a dormant state in most soils until prompted into action by stressors or mechanical damage or contamination. Japanese maples are extremely prone to it - they are not tolerant of stress factors (climate, drought, poor drainage, etc.) and have a delicate root system that is easily damaged, which can lead to infection by the pathogen.

I'm going to disagree with Dan re: the perched water table. Generally mounded soil - small berms - provide very good drainage and PWT's are not a factor. In all my years of landscaping, I've yet to see this be an issue. In fact, this is a recommended planting method for those dealing with heavy clay soils. It may be more likely that mounded soil drains so well, the tree may not be getting enough water :-)

btw, cutting back the old fronds on the ferns annually in late winter just as the new growth emerges will keep them looking lush and green. It actually encourages additional growth.

Thanks again for the discussion folks. Even though no direct remedy found because the nature of my problem it's nice to dissect problems on this web with the community. Thanks again.

GG: when I lived in CA I used to contribute to the CA Tree Failure Report. One of the boxes on the checklist is 'Mound Planting'. For the very reason I described above. If you incorporate new into native, there is no problem. If you slap down new texture on top of old and call it good, then the landscaper comes along and plops down some tree and calls it good, years later you have professors taking out urban forestry students to mound plantings to show you what happens with improper technique. Common in CA GCV. And scales down.

Nonetheless, this is not to say that is what happened here. Harsh winter, mostly shade are main culprits in my view. There may be VW, which will likely finish the tree this year if so, and not much to do to prevent succumbing. I'd just prune off dead (as you do every year with this tree) and call it good. YMMV.

BTW, to the OP: fertilizer won't help you. Spend the money on something else.

Dan

also there was once very cold night when we were expecting snow. snow didn't happen but i think it was very close to freezing point.

===>>>> if it was enlarging its buds.. and the cold hit... then that might be the problem ... its what happens up here all the time with JM

if its a one time thing.. there is a chance that it might rebud.. but that would take some time ... as such i would hesitate to cut down the dead looking parts ... until i was sure ... and i am unsure when that is in your zone ... probably the limit of your patience with it ...

the upside of doing it sooner .. is that you focus the energy on the healthy parts.. rather than let it struggle to rebud ...

you are going to have to learn about pruning.. to reshape it in the future .. and that would just be about training it back into a form that pleases you ...

good luck

ken

Interesting discussion regarding mounding...

Dan, what do you mean by the following:

I expect tiny little mounds to have perched water tables if the mound wasn't incorporated into native.

If you incorporate new into native, there is no problem. If you slap down new texture on top of old and call it good...

Does this just mean you need to use a similar textured soil when mounding for a planting to ensure proper settling and water distribution?

whaas
I think what Dan meant is mixing in new soil with native into some depth instead just taping the new mound on surface. And guess yes, you should be using similar texture. That's my common sense non-academic guess.

Dan, we may just have to agree to disagree on this subject :-) Elevated soil levels - berms, mounds, raised beds - are typically characterized by fast drainage (sometimes too fast) without any incorporation of existing soil. Unless an unnaturally high water table exists, a PTA is not involved.

I have built or spec'd countless mounded or bermed planting areas in my years as a landscape designer to compenstate for dealing with heavy clay soils (and without incorporating any existing soil into the bermed material) and I've yet to experience one that created a PTA or did not improve drainage and hasten establishment of trees and shrubs that would otherwise suffer from the lack of drainage and aeration direct planting in clay/poor drainage would offer. And if I remember my college classes in soil science, I don't recall this being a topic of concern with mounds or berms either :-)

This concept is pretty well supported by a host of reputable sources, including SULIS, UGA Center for Urban Agriculture, various state extension services, George Ware (dendrologist for the Morton Arboretum), Whitcomb, etc., not to mention a bunch of other landcaping, tree planting and nursery sites. There may be some unique or isolated cases where this may not be an ideal practice, but in general, mounding or berming does not create a PTA but rather discourages the formation of unfavorable drainage issues.

I would not consider the OP's mounded planting to be a contributing factor the the tree's current distress unless the drainage was sufficiently fast to the point of the mound drying excessively in summer. And that can be a concern and could be a contributor to drought stress which could lead to other issues.

It looks like it has a bad crotch that may be separating from the other leader limiting sap flow. The left side looks dead from there on up.
I would have passed over it for another one on the sales lot.
Mike