Heat damage?

[HankB]

End of March:

DSC_1826_PP

• HankB
• Mar 31, 2017

Sunday morning

DSC_0999-PP

• HankB
• May 16, 2017

Everything looked fine when we left the house Friday afternoon. By Sunday morning this is what I saw. I checked soil moisture (using one of those cheap probe gauges) and it was OK. (I tend to keep all of my plants on the dry side and it read in the dry range.) I guess this resulted from heat. Temperature Saturday was into the 80s and I had this on a brick patio where it probably got hotter. Last summer I had it elevated where it got better air circulation and must have remained cooler.

I've kept it out of the sun since then and watered a bit. Is there anything I should be doing to support recovery (if it is even still alive?) Foliage is various shades from brown to green so I hope the green parts can recover.

Thanks!

edit: substitute pictures from gallery.

 

[Dav4]

There aren't many places in the US where junipers can't tolerate full sun, assuming this has been outside right along. Granted, reflected heat and a dry root ball can cook almost any tree. My money is on either spider mites or dried out foliage. Either way, get it back into the sun in a place where it won't have reflected heat and keep it watered appropriately.

 

[HankB]

There aren't many places in the US where junipers can't tolerate full sun, assuming this has been outside right along. Granted, reflected heat and a dry root ball can cook almost any tree. My money is on either spider mites or dried out foliage. Either way, get it back into the sun in a place where it won't have reflected heat and keep it watered appropriately.

Yes, outside since I got it about a year ago.

Could spider mites cause that much damage in ~2 days? I'll have to look that up.

Back in the sun and I'll monitor moisture.

Thanks!

 

[Dav4]

Yes, outside since I got it about a year ago.

Could spider mites cause that much damage in ~2 days? I'll have to look that up.

Back in the sun and I'll monitor moisture.

Thanks!

Spider mite damage does show up "overnight" even though the mites have been sucking on the foliage for weeks or even months. I suspect you probably cooked the new foliage, but you should check for mites either way. Good luck with it.

 

[VAFisher]

You can already see that all the tips are brown in the March photo. So whatever the problem is didn't start 2 days ago.

 

[HankB]

You can already see that all the tips are brown in the March photo. So whatever the problem is didn't start 2 days ago.

Interesting observation. I had noticed the change in color but didn't associate it with a problem. This thing seems to change color through the seasons. I've been watching for signs of spring growth and haven't really seen any. It did put out about an inch of terminal growth last summer and it seemed like it was late in summer. Should I be seeing a flush of spring growth and if not, how should I respond?

 

[VAFisher]

I'm no expert but I would think you should be seeing fresh new light green growth by now. I would follow Dav4's advice and check it for mites.

 

[HankB]

I'm no expert but I would think you should be seeing fresh new light green growth by now. I would follow Dav4's advice and check it for mites.

I've inspected it carefully and can find no evidence of mites. It's back in the sun. I'll be watering when the soil surface becomes dry. I watered a bit yesterday and soil surface has not yet dry.

Thanks!

 

[Relknes]

Interesting observation. I had noticed the change in color but didn't associate it with a problem. This thing seems to change color through the seasons. I've been watching for signs of spring growth and haven't really seen any. It did put out about an inch of terminal growth last summer and it seemed like it was late in summer. Should I be seeing a flush of spring growth and if not, how should I respond?

You should definately have seen some new growth by now. The fact that you haven't seen any is a pretty clear sign something is wrong. Junipers are notorious for keeping their color for weeks or months after the plant is dead. Often by the time you notice browning it is pretty far gone. I would guess that by the time the first picture was taken your tree was in some level of distress already.
Feel the foliage. If the green parts are dry and stiff, there is a good chance it is already dead. If they are springy and soft, it is still alive.

 

[HankB]

Feel the foliage. If the green parts are dry and stiff, there is a good chance it is already dead. If they are springy and soft, it is still alive.

Inner parts still feel springy.
I wonder if putting it in the ground would be helpful? Repotting?

 

[Relknes]

Inner parts still feel springy.
I wonder if putting it in the ground would be helpful? Repotting?

Repotting a weak tree is asking for trouble. It can be necessary at times, but only if the soil is the problem.
Most likely, I would guess that you either over watered it or under watered it. If that's the case, the best thing is to get in in the proper conditions and hope it recovers.

 

[Saddler]

I have "closely inspected" for spider mites and killed a few trees because I was looking for them in the foliage and not on the paper. What I mean is, did you put a piece of white paper under the tree and give the tree a good tap or three and look for movement on the paper? I thought because I could find mites on my house plants easy enough, I could find them on my cypress and juniper, ha! That $750 dollars in lessons almost took me out of bonsai. Now I check all my trees at the beginning of every month from May to October.

 

[Cypress187]

Repotting a weak tree is asking for trouble.

I think he also said ground, maybe slipping(aka no root-work) it into the ground could be thing? I don't know much about them, I only seem to kill them.

 

[chicago1980]

Could this be tip blight?

 

[HankB]

I have "closely inspected" for spider mites and killed a few trees because I was looking for them in the foliage and not on the paper. What I mean is, did you put a piece of white paper under the tree and give the tree a good tap or three and look for movement on the paper? I thought because I could find mites on my house plants easy enough, I could find them on my cypress and juniper, ha! That $750 dollars in lessons almost took me out of bonsai. Now I check all my trees at the beginning of every month from May to October.

I did this test and in addition to some dropping branch trips I saw one red spider mite and something that looked like a thrip. My initial inspection showed none of the web-like detritus described as a symptom of mites. I saw that one treatment for mites is a forceful water spray so I did that.

Could this be tip blight?

I saw some descriptions of blight that indicated it started on a portion of the plant and then spread. This is not the picture I see. Ate there other symptoms I should be looking for?

Thanks!

 

[Saddler]

I would get a mite/insecticide and nuke them. After trying all kinds of friendlier methods, water spray, soap, neem oil, tobacco tea spray and a combination of all of them at once, nothing works nearly as well a miticide. With all the nooks and crannies in a juniper, it can be particularly difficult to get complete coverage.

 

[HankB]

Junipers are notorious for keeping their color for weeks or months after the plant is dead.

I'm pretty much convinced this is the situation. The bark on the trunk is splitting. I peeled a bit back and there is nothing green under the bark. I guess it didn't make it through the winter and it just took me a while to realize that.

 

[dirk hoorelbeke]

Not mentioned before. Watch out with dark pot in full sun. It is possible that boiling a tree is counterproductive. In hot climates (not ours) aluminum foil is used to cope with this.

 

[HankB]

Not mentioned before. Watch out with dark pot in full sun. It is possible that boiling a tree is counterproductive. In hot climates (not ours) aluminum foil is used to cope with this.

Thanks for the tip. I will probably get another juniper and have another go at this.