shimpaku branches dropping

[watchndsky]

Ive lost several branches on 3 trees over last year and a half - one was a total loss. Ive got the same discoloration on another and dont want to lose anymore.

Soil is largely inorganic, with mix of some brussels type soil and large percentage of chicken grit from the mill. Ive treated with daconil on others at first sign, theres been no indication of mites, no changes in watering style (had these for many years), no sign of root rot, foiliage starts to turn a greyish color, and sometimes after removal no other areas are affected - sometimes wind up losing whole branch. Can anyone tell me whats going on? If this is fungal am I not being aggressive enough in treatment or something?

 

[watchndsky]

 

[barrosinc]

did you bend that branch lately?

 

[watchndsky]

no - sorry forgot to mention that - no bends - no physical damage (and this has occurred on more than one branch on more than one tree) so I know that can be the issue.

 

[barrosinc]

ok, so I am out of ideas now... Junipers can do that... bend too much and months later - BOOM - dead branch

 

[markyscott]

Any chemicals?

Scott

 

[Brian Van Fleet]

Spider Mites...or it got bumped and snapped.

 

[watchndsky]

no possibilities of brush killers roundup, etc - last chemical sprayed was daconil (as preventative) and that was last fall.

hoses, sprayers etc have not been hooked up yet (too early with late frosts etc) so watering has been by hand and not overhead thru foliage.

no sign of physical damage (squirrels chipmunks etc)

 

[watchndsky]

never any sign of mites on any of them- was first thing i checked.

in fact - ive never see any insect damage in years on any of my trees. (except for those little green worms that appeared out of nowhere and ate part of a mugo).

 

[Brian Van Fleet]

Well...sometimes s#!t happens.

 

[Dav4]

I've had spider mites do that to a branch...I could find them the year before (the branch did turn a noticeably unhealthy color one week in June which alerted me to the infestation). The branch turned brown and crispy the following spring.

 

[Cadillactaste]

No advice...but so sorry to see your dealing with that.

 

[0soyoung]

Ive lost several branches on 3 trees over last year and a half - one was a total loss

So what did you see in the wood you cut off? Any stains? Uniform white(ish) color? Nice tan color?

 

[watchndsky]

you know- didnt think of that back then - will check inside the wood for this one when i sever.

it always gets me how long foliage stays green when you chop something off - but when dies on its on it does with so little warning.

so the branch didnt die recently -its been dead weeks/months. These junipers did well for 8 years until the last season. just dont know what the issue is or how its seemed to "spread" to others juni's.

maybe i should proactively spray fungicide and miticide all year round?

 

[Stan Kengai]

Borers?

 

[0soyoung]

you know- didnt think of that back then - will check inside the wood for this one when i sever.

it always gets me how long foliage stays green when you chop something off - but when dies on its on it does with so little warning.

so the branch didnt die recently -its been dead weeks/months. These junipers did well for 8 years until the last season. just dont know what the issue is or how its seemed to "spread" to others juni's.

maybe i should proactively spray fungicide and miticide all year round?

I think it pays to do a little autopsy on everything that gets removed for any reason other than normal pruning/styling. Even then it is good to do the first few times so that you develop some understanding of how normal wood appears.

Recall how trees work. Water and nutrients go up in the wood (xylem). Photosynthate goes down the tree in the phloem (aka secondary bark). Removing in the phloem does not, in itself, kill a branch (we do this to make air-layers).

A branch dies because something causes the xylem to get plugged up.

Thus, branch death caused by something below (i.e., closer to the roots) the dead region. In other words, you want to remove a bit more than what is obviously dead. A pathogen that causes sudden death of the cambium will provoke a natural damage response which will, inturn cause a corresponding part of the xylem to clog up. But this will be obvious by gooey/loose/darkened bark. Still, remove a bit more than what is obviously affected.

Certainly pathogens can be spread from one tree to another by pruning tools. Sanitize the tool with (70%) isopropyl alcohol (or a standard bleach solution) after every cut when you are fighting issues like this.

Otherwise, I suggest that you list everything the affected trees have in common and also write down notes about what the problem is and is not (e.g., is not gooey bark, is yellowing foliage, is not the entire tree, is just one branch, is only junipers, is not maples, is junipers wintered on the north forty, is not junipers in the front yard).

 

[CamdenJim]

Well...sometimes s#!t happens.

Yes. The bumper sticker is right.
I've lost primary branches on two azaleas, with no cause I can find other than this.