shimpaku with dying tips! please help!

[pspees]

Anyone tried something like this? Did a little research and came up with a recipe for killing mites:

http://www.mellobonsai.com/care/Miticide.aspx

I just did this yesterday. We'll see how well it works.

 

[Brian Van Fleet]

Anyone tried something like this? Did a little research and came up with a recipe for killing mites:

http://www.mellobonsai.com/care/Miticide.aspx

I just did this yesterday. We'll see how well it works.

That should work. I was a big fan of Paul James the Gardner Guy, and he used a solution like that. I'd be a bit careful about keeping it out of a lot of sun for a few days. The dish detergent may accelerate transpiration for a while.

FWIW, lots of better websites are out there with excellent articles and tips. in the event this wasn't a stumbled-upon link, be sure to also check out sites such as:

www.bjorvalabonsaistudio.com
www.evergreengardenworks.com
http://japanesebonsaipots.net
http://bonsaitonight.com
http://crataegus.com (just did a post today about pinching junipers...the OP subject. Great post!)
http://bonsaiunearthed.com/
http://peterteabonsai.wordpress.com
http://saruyama-bonsai.blogspot.com/

 

[davetree]

When I worked in the commercial indoor landscaping trade, this was the standard formula that kills mites and many other bugs. Safe, non toxic, cheap and effective. Alcohol can dry some leaves, so on some species follow application with water rinse/spray and keep out of strong sun.

 

[pspees]

Still dying

Okay so I'm really sad to say that I just can't seem to fix this problem. I would really like to but now I'm thinking that I won't be able to save this tree in time before too much of the foliage dies. I've lost quite a bit of foliage now. No mites, no more poor drainage in the soil, no soggy overwatered soil. I went ahead and repotted a few weeks ago and twisted off all the dead needles and it just keeps happening. I figured that the tree would be dead by now had the repot been unsuccessful but a lot of the tree does have some nice (slow) growth at the healthy parts. It's just that so much is still turning brown. Last thing I can think of is fungus. That or how hot it has been these last few weeks. Should I zap it with chemicals at this point? What do you think?

 

[Vance Wood]

I probably have a dozen or more Shimpakus ranging in sizes from six inches or less to twenty-four inches and more. I have seen this problem come and go on trees that are treated more or less the same and it always goes away. Sometimes it helps to move the tree into a more shaded location for a week or two. I think a good portion of the issue is more one of heat than anything else, I would put water next but there seems to be no one solution I know of.

I do have a question for some of you Shimp masters: Have you ever seen scale on a Shimpaku and what does it look like.

A good question, I believe I have had it and have not found a really good way to deal with it that does not cause the tree a lot of difficulty.

 

[fore]

I made a note in post #8 about tip blight. Try treating for this...what else do you have to lose? jmho.

 

[bonsaibp]

I would say that it's almost definitely from root rot. I've seen this many times. Tip blight is almost always on trees east of the Missippi, I've never seen it in CA. Try talking to Fred Miahara from the San Deigo Bonsai club he's an expert on shimpaku's.

 

[Brian Van Fleet]

It might be past the point of no return, usually the damage is done before the symptoms really present. But, here is another article on the subject that you should read: http://peterteabonsai.wordpress.com/2011/11/10/shimpaku-health/
Unfortunately, I have a small juniper I'm trying this technique with. It seems to have suffered from a similar plight as the one in Peter's post, so I moved it to 100% "sand" for the remainder of the year, until I can repot it next spring. In the 2 months since shifting it to sand, it has begun to improve, and continue to grow. Prior to this, I have only won the battle with root rot once or twice.

 

[pspees]

Some more pics to show what's going on

 

[Brian Van Fleet]

Still looks like it's ok, but in too-wet soil. Place a wedge or rock or something under one side of the pot to tilt it up an inch or two to help water runoff. Switch it to the other side every week or two, then as soon as its reasonable to repot in your area, get some help repotting it into a coarse, less-or inorganic soil mix.

 

[Vance Wood]

It is also possible that the tree is root bound and the outside roots in contact with the pot are starting to fry. I have had trees do this and usually repotting solves the problem. That's not saying this is your problem but if the tree has been in the pot for a long time you might want to consider it.

 

[pspees]

Thanks guysI repotted it about three weeks ago and loosened up much of the root ball (except under the base/trunk, that part is still pretty tight and holds too much moisture). It was very tight in the pot and drainage was definitely an issue. The soil it's in now is about one third organic to two thirds inorganic. 1 part scoria, one part pumice, and 1 part bonsai mix. Drains very quickly but still holds moisture for a few days. I wonder if I just need to let it dry out some more between watering but I don't want to let a newly repotted tree get too dry especially since it's been pretty hot. The base of the trunk stays a little damp while the rest of the pot seems to be dry so I've been watering it then. I do keep it in the shade during the afternoon. Hope this helps!!

 

[bonsaibp]

Yes let it dry out fairly well. Not bone dry but not very moist either. Staying wet a few days with the heat we've had say the roots aren't taking up moisture very well. I'd give it good morning sun and keep it out of the winds.

 

[Smoke]

Dead roots. Pot probably got too hot and killed off too many hairlets. Some of the best pine people in Cali are in San Diego. Do what Rock says and get with him. I think he goes by Big Dave.

 

[bonsaibp]

In regards to getting rid of spider mites:

Try an oil spray first - they are like microscopic aphids and they suck sap from the tree. If you only have a couple small trees then you should be able to saturate them with an oil spray. The good thing about oil is that it suffocates the insects - so they can't really develop resistance to it. If you have more trees or the oil spray doesn't get rid of them then switch to malathion, orthonex or bayer shrub and tree care, or look for a specific miticide. Those are systemic chemicals which the tree will metabolize and then when the mites such sap it will kill them. Spider mites have about a 10-day life cycle so you need to re-spray the tree two more times at ten day intervals to catch mites that are hatching after you sprayed. Alternating with two or even three insecticides helps ensure that the mites don't build resistance. Make sure you spray everything that you have, not just the infected tree. They are wind blown and can easily re-infect a tree. If you have large conifers like Italian Cypress, pine or similar in your neighborhood that are infected you will have an ongoing problem.

Overhead watering with a good spray of water discourages small infestations from getting large by washing them off the plant, but once they get established the water method doesn't work. I would recommend that you overhead water your tree at least a couple times a week, not misting, but a good overhead spray to rinse things off.

regarding Shimpaku and scale - I've seen small white scale infect shimpaku. They're not particularly damaging to the trees in my experience, they usually attach the weaker growth and shaded areas. They look like little spots of sap. If you flick the branch you might see small white flakes fall off. The same type infects procumbens and it seems to prefer procumbens but it generally only weakens branches a little, it doesn't kill them like spider mites do (at least in my experience.)

If you ever need to treat for mites oil sprays are great but wait until the weather cools down considerably. It's been in the 90's to low 100's in Southern CA the past month or so.
Also Bayer tree and shrub does not kill mites but they do make a miticide.

 

[pspees]

Just wanted to follow up...

Browning seems to have slowed down. The needles that are dying off seem to only be older growth-more so at the bottom section of the tree. I figure that whatever roots died/got pruned corresponded to the foliage that died. Most of the new stuff and top half is not really affected. Typical? Also, I've been letting the pot dry out more. It was staying too wet and water was wicking it's way up the trunk so I started watering less. Anyway, the problem now is that when I repotted I left about a 6" diameter mass of the old soil intact under the nebari. That area is still very tight and I was afraid that if I got into it it would kill the tree so I just left it. Looks like old broken down akadama and STAYS TOO WET. That was probably the problem all along; too much water at the core of the roots. When the outer soil would dry out it prompted me to give it more water and the core stayed really wet. I'm just afraid that too much damage was done and that the roots might continue to die. So with that in mind I've been lightly watering (juust enough) outside of the dense part and the tree seems to be happier. Now it appears that the healthy foliage has livened up a bit more and the tree seems to be doing a little better. Should I cut off anything that's still turning brown?

Any more advice on dealing with this is greatly appreciated! Thanks for the help!

 

[bonsaibp]

For now you can use a peice of rebar or whatever and make some holes down into the old soil. Fill those holes with your bomsai mix. At the next transplanting remove 1/3 to 1/2 of the old soil and at the next repotting remove the rest. It can be problematic (dead tree) if you try to remove all at one time. This is a very common problem.

 

[Vance Wood]

For now you can use a peice of rebar or whatever and make some holes down into the old soil. Fill those holes with your bomsai mix. At the next transplanting remove 1/3 to 1/2 of the old soil and at the next repotting remove the rest. It can be problematic (dead tree) if you try to remove all at one time. This is a very common problem.

I agree but I wouldn't use a piece of rebar, it's too large. I have done this with an awl or narrow screw driver. As for now I would leave the tree alone. Shimps are very tough---to a point, but if you keep fooling around with it you might lose it.

 

[bonsaibp]

I said rebar because we have a sharpened piece of 1/4" rebar I use at the nursery for this. It's probably more like 3/8's after the grinding. A screwdriver may be more appropiate in this case.

 

[Vance Wood]

I said rebar because we have a sharpened piece of 1/4" rebar I use at the nursery for this. It's probably more like 3/8's after the grinding. A screwdriver may be more appropiate in this case.

I didn't mean to nit pick your advice. I've seen the results of people taking things too literally when they really didn't understand the reason for the advise. In this case it is far easier and far safer for the tree that a smaller tool is used, there is less chance for damaging a critical root. That doesn't change the fact that you were right in principal and intent.