Ummm... Help... Need Second Opinion/Diagnosis???

[brewmeister83]

I've had this Chinensis for about two years... Re-potted when I first got it to get it out of the garden soil it was in, and just re-potted about five weeks ago into a more freely draining inorganic mix.

I've been battling a small case of rust through pruning only since I got it, but this year I took to using a half-strength copper fungicide after gall removal since I didn't want it to loose any more foliage/branches - that was about 2-3 weeks ago.

About a week after I treated it, it started to show signs of yellowing at the tips - I thought I had perhaps inadvertently used too much copper, even at half strength, causing phytotoxicity so I rinsed the foliage really well and flushed the pot several times to remove any trace residue.

Since then it's been yellowing more, and some of the tips have started to redden. I checked a couple internet resources - and from what I've read I've narrowed it down to either Phomopsis or Kabatina twig blight. Thoughts anyone? I really don't want to loose this plant, it's my first juni since starting bonsai

 

[Jester217300]

What's your soil mix? I'm inclined to think it's from the repot. I haven't had much of a problem taking juniper roots back hard so my guess would be overwatering, possibly due to soil substrate.

 

[brewmeister83]

1/8" screened and washed DE - this plant has been in it since the moment I got it and showed no adverse reactions to it or my watering schedule all last year. The only reason I re-potted it this year was because (being a complete newbie two years ago) the soil was not sifted or washed last time. After two years it started to not drain as easily after watering so I opted to remove it before the smaller silt-sized particles started causing more watering problems and/or root rot in the pot. The roots were not pruned at all, just lightly combed out to remove the finer particle sediment. If anything this means that less water is now staying in the pot that before, so I'm inclined to not think it's overwatering.

 

[Jester217300]

DE has a tendency of becoming hydrophobic in unpredictable ways. The fact that it was becoming hard to water reinforces that idea. I still think it's possible that the previous conditions were better and the repot is somehow allowing more water to stay in the root zone. DE is a little tricky and at 100% it's probably the least reliable substrate (along with calcined clay, effectively the same). The pot is pretty deep and small size DE holds a lot of water. 5 weeks is almost a text book amount of time to look back for the cause of an unhappy juniper and yellowing tips is a very classic sign of overwatering. I would be extremely surprised of the bottom of that pot dries by the time the top needs water.

 

[0soyoung]

If it is 'too wet' (maybe) sit the pot on a slant (i.e., tilt it 15 to 30 degrees, say, and leave it that way for a while). Immediately after watering, tip the pot as close to vertical as you can without pouring out the medium - hold it that way until water quits running out, then return it to its slanted resting position.

A one time root drench with 2 tablespoonw (3%) hydrogen peroxide in a quart of water will wipe out phytophthora (and most any other baddies eating the roots - apply drench and the tip pot up to drain).

Good luck.

 

[brewmeister83]

DE has a tendency of becoming hydrophobic in unpredictable ways. The fact that it was becoming hard to water reinforces that idea. I still think it's possible that the previous conditions were better and the repot is somehow allowing more water to stay in the root zone. DE is a little tricky and at 100% it's probably the least reliable substrate (along with calcined clay, effectively the same). The pot is pretty deep and small size DE holds a lot of water. 5 weeks is almost a text book amount of time to look back for the cause of an unhappy juniper and yellowing tips is a very classic sign of overwatering. I would be extremely surprised of the bottom of that pot dries by the time the top needs water.

I haven't had any problems before with DE becoming hydrophobic, I'd be interested in reading up on this phenomena if you could point me to the article where you came across this info. As far as why it was becoming harder to water it, I already identified the problem in post # 3.

If it is 'too wet' (maybe) sit the pot on a slant (i.e., tilt it 15 to 30 degrees, say, and leave it that way for a while). Immediately after watering, tip the pot as close to vertical as you can without pouring out the medium - hold it that way until water quits running out, then return it to its slanted resting position.

A one time root drench with 2 tablespoonw (3%) hydrogen peroxide in a quart of water will wipe out phytophthora (and most any other baddies eating the roots - apply drench and the tip pot up to drain).

Good luck.

I'm a little confused by this advice, are you saying the problem lies with the roots and they need to be treated? The pot drains free whenever I water it thanks to several inch wide drainage holes, and after watering it in the morning the top 1-2 inches of substrate are bone dry by the time I get home from work in the afternoon (the pot is 7 inches deep). I didn't think overwatering was the issue here... if anything, now that the substrate drains freely, there's less water in the soil than last year. Am I wrong in thinking this?

 

[M. Frary]

DE has a tendency of becoming hydrophobic in unpredictable ways. The fact that it was becoming hard to water reinforces that idea. I still think it's possible that the previous conditions were better and the repot is somehow allowing more water to stay in the root zone. DE is a little tricky and at 100% it's probably the least reliable substrate (along with calcined clay, effectively the same). The pot is pretty deep and small size DE holds a lot of water. 5 weeks is almost a text book amount of time to look back for the cause of an unhappy juniper and yellowing tips is a very classic sign of overwatering. I would be extremely surprised of the bottom of that pot dries by the time the top needs water.

Been using D.E. for a while now. I haven't had a single problem yet.

 

[Eric Group]

Spider Mites. Check the tree for them, apply nasty chemicals if present.

Otherwise, I believe the copper would be the way to go for most of the illnesses that affect these guys.. I didn't see you mention that you had checked for the mites yet, and generally when Junis start dropping color tones like this (and it isn't soon after a repot), it is a sign something is attacking them- insect or disease. If you treated disease, insect is most likely the culprit, if you cannot see the bugs doing it, they are prolly too small to see.. Like MITES! Put a piece of white paper under the tree, shake the branches real good and see if tiny microscopic dots are moving around on the paper after. Get a magnifying glass if needed... If you can see them, you need to spray this sucker- they will get out of hand and kill your tree fast.

Quarantine it til you figure out the issue just to be safe.

Good luck!

 

[0soyoung]

are you saying the problem lies with the roots and they need to be treated?

I was and am saying IF (hence 'maybe' parenthetically in my repsonse) - just an offer of a tool for your horlticultural tool box. I now see that I overlooked you first photo - I had a shallow pot in mind, not a cascade.

Just to review how I understand your original dialog

• repotted into DE 2 years ago
• pruning off branches affected by rust for last 2 years (maybe longer)
• started spraying Cu 2-3 weeks ago as a rust preventive
  • a week after first spaying Cu (i.e., 1-2 weeks ago) saw first yellowing tip
  • stopped spraying Cu
• washed foliage and flushed the pot of DE (about 1-2 weeks ago)
• yellowing has since gotten worse and tips are beginning to redden
• now you think your tree's problem is Phomopsis or Kabatina twig blight

Chemical control of these tip blight diseases normally is not necessary in established landscape or windbreak plantings. Occasionally, fungicide applications may be needed on susceptible junipers to control Phomopsis blight. Application of certain copper-based fungicides (Phyton-27, Kocide), thiophanate-methyl (Cleary's 3336, Domain, Fungo FLO), or mancozeb (Fore, Dithane, mancozeb) at 7- to 21-day intervals during rapid plant growth in the spring will give adequate control of Phomopsis but not Kabatina tip blight. Kabatina blight infections occur in the fall, and there currently are no fungicides labeled for control of this disease

So, my thoughts are

• not Phomopsis because Cu fungicide is its remedy (i.e., spraying Cu would NOT induce a Phomosis infection)
• not Kabatina because Kabatina blight infections occur in the fall - it was spring when the tip yellowing first appeared 2-3 weeks ago.
• when was the last time you administered some fertilizer?

 

[GrimLore]

I didn't see you mention that you had checked for the mites yet, and generally when Junis start dropping color tones like this (and it isn't soon after a repot), it is a sign something is attacking them- insect or disease.

If you look very closely at the second picture expanded there are tiny white specks all over the new growth. I concur - time for bug warfare...

Grimmy

 

[brewmeister83]

I was and am saying IF (hence 'maybe' parenthetically in my repsonse) - just an offer of a tool for your horlticultural tool box. I now see that I overlooked you first photo - I had a shallow pot in mind, not a cascade.

Just to review how I understand your original dialog

• repotted into DE 2 years ago
• pruning off branches affected by rust for last 2 years (maybe longer)
• started spraying Cu 2-3 weeks ago as a rust preventive
  • a week after first spaying Cu (i.e., 1-2 weeks ago) saw first yellowing tip
  • stopped spraying Cu
• washed foliage and flushed the pot of DE (about 1-2 weeks ago)
• yellowing has since gotten worse and tips are beginning to redden
• now you think your tree's problem is Phomopsis or Kabatina twig blight

So, my thoughts are

• not Phomopsis because Cu fungicide is its remedy (i.e., spraying Cu would NOT induce a Phomosis infection)
• not Kabatina because Kabatina blight infections occur in the fall - it was spring when the tip yellowing first appeared 2-3 weeks ago.
• when was the last time you administered some fertilizer?

was not aware kabatina was only in fall, my source didn't indicate this, thanks for the info... Fertilized weekly since March with half strength fish emulsion/seaweed liquid. I also give it a twice-yearly dose of miracid for acidity and nutrients as per label instructions, but have yet to give it its spring dose b/c of this.

 

[brewmeister83]

Spider Mites. Check the tree for them, apply nasty chemicals if present.

Otherwise, I believe the copper would be the way to go for most of the illnesses that affect these guys.. I didn't see you mention that you had checked for the mites yet, and generally when Junis start dropping color tones like this (and it isn't soon after a repot), it is a sign something is attacking them- insect or disease. If you treated disease, insect is most likely the culprit, if you cannot see the bugs doing it, they are prolly too small to see.. Like MITES! Put a piece of white paper under the tree, shake the branches real good and see if tiny microscopic dots are moving around on the paper after. Get a magnifying glass if needed... If you can see them, you need to spray this sucker- they will get out of hand and kill your tree fast.

Quarantine it til you figure out the issue just to be safe.

Good luck!

Did the paper test, didn't see signs of mites, but I did get some small black aphids - treated plant for these pests, I figure if there are mites I missed with the test I'll get them anyway. Don't spidermites make webbing? I haven't seen any on this juni so far.

 

[Eric Group]

Did the paper test, didn't see signs of mites, but I did get some small black aphids - treated plant for these pests, I figure if there are mites I missed with the test I'll get them anyway. Don't spidermites make webbing? I haven't seen any on this juni so far.

They do make fine weds sometimes I think... If there are none present, you saw no moving dots... Maybe not spider mites, but aphids will drain a tree just about as fast and if well blended with the foliage can be just as hard to see! They can also cause all sorts of fungal issues- that honeydoo stuff they poop everywhere must cause it to spread or something? I think I read that somewhere. I try to never let them hang around long enough to find out!

 

[brewmeister83]

They do make fine weds sometimes I think... If there are none present, you saw no moving dots... Maybe not spider mites, but aphids will drain a tree just about as fast and if well blended with the foliage can be just as hard to see! They can also cause all sorts of fungal issues- that honeydoo stuff they poop everywhere must cause it to spread or something? I think I read that somewhere. I try to never let them hang around long enough to find out!

hmmm... maybe leaf yellowing is virus or something brought in by the aphids? either way, they're already toast! now I just need to see if this plant recovers

 

[GrimLore]

hmmm... maybe leaf yellowing is virus or something brought in by the aphids? either way, they're already toast! now I just need to see if this plant recovers

Aphids, if that is what they are eat ate the base of the newest or most ender part of the foliage. They usually don't show up until there is tender offerings and in my area they usually do not stick around long. When they are present you will usually see a lot of ant activity on your plant. I BLAST all of the foliage with the hose, let it dry and then treat the plant. The most I have ever had to do that is twice in a season and only on a few plants. Some insects can and do leave a residue that fungal disease(various types/various critters) feeds on. By taking quick action with the hose and a simple treatment will safeguard your plants quickly and effectively.

Grimmy