Help JBP - Dothistroma needle blight

Clicio

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After some research, I think this is the disease that is making the low needles of my cascade cork bark JBP fall down.
It's been a hot and very humid summer here, and the tree is getting its fair amount of rain showers every day. Other JBP I have nearby seem not affected by the same symptoms, and look healthy.
So, the diagnosis seems to be:
"Dothistroma needle blight is a fungal disease that turns needles brown and results in early needle drop. Needle loss slows tree growth and severe infection several years in a row can result in tree death."
Below is a picture to help your confirmation, and some more info.
The questions are:
Is Daconil effective against this problem?
What else should I do besides following the advice below?
  • Do not overcrowd plants.
  • Remove bottom most branches from trunk to help increase circulation around the tree canopy.
  • Control weeds under the trees with wood mulch.
  • Maintain a layer of mulch around your tree. Do not mound the mulch around the trunk of the tree but lay a flat layer.
  • Make sure that water is not spraying the needles.
  • If the disease does occur, a copper fungicide can be applied once just before buds open in the spring (typically in mid-May) to protect needles from previous years and once after new needles have grown to their full length (in early to mid summer).
@sorce , should I just BURN IT?
APC_0164.jpg
 

Clicio

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Thanks, scales I think is possible. Been fighting against them for some time now.
But mites? I have never had mites on any of my trees. I'll check it out.
 

just.wing.it

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I think I see scale insects too...
As far as other issues, I'm no disease expert...
I guess I'd focus on the scale bugs first...and proceed from there.
 

Clicio

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When the seeds arrive, they could die from contamination as they germinate.
Anthony
They go to a different site, @Anthony . This tree is isolated and kilometres away from the place I will sow the seeds.
Thanks for your concern!
 

AJL

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Here in England , Dothistroma is currently the most significant disease of coniferous trees, also known as Red band needle blight, the name describes the symptoms well: reddish brown banding on the needles which then progressively die and drop off the branches leaving a characteristic tuft of surviving needles on the shoot tips, looking like a lions tail
1521224462007.png 1521224530485.png1521224641507.png1521224462007.png1521224530485.png1521224641507.png
Cant make out clear symptoms from your photo- only small scale insects:could you post photos showing more symptoms?
 

Clicio

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Here in England , Dothistroma is currently the most significant disease of coniferous trees, also known as Red band needle blight, the name describes the symptoms well: reddish brown banding on the needles which then progressively die and drop off the branches leaving a characteristic tuft of surviving needles on the shoot tips, looking like a lions tail
Cant make out clear symptoms from your photo- only small scale insects:could you post photos showing more symptoms?

Yes, @AJL thank you! Now how to get rid of this plague?
The "scales" I've been dealing so far are much bigger than the microscopic white dots I see on these needles, but I am not sure.
So for the pictures:

First, I have shaken the needles on a white sheet of paper; many small things are there (surprise!), but none crawling or moving as far as I can see without a loupe.APC_0166.jpg

Then The needles, from far to close up:
APC_0171.jpg

APC_0169.jpg


Sorry for this one below, , it's a crop from a cellphone
APC_0170.jpg
 

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After some research, I think this is the disease that is making the low needles of my cascade cork bark JBP fall down.
It's been a hot and very humid summer here, and the tree is getting its fair amount of rain showers every day. Other JBP I have nearby seem not affected by the same symptoms, and look healthy.
So, the diagnosis seems to be:
"Dothistroma needle blight is a fungal disease that turns needles brown and results in early needle drop. Needle loss slows tree growth and severe infection several years in a row can result in tree death."
Below is a picture to help your confirmation, and some more info.
The questions are:
Is Daconil effective against this problem?
What else should I do besides following the advice below?
  • Do not overcrowd plants.
  • Remove bottom most branches from trunk to help increase circulation around the tree canopy.
  • Control weeds under the trees with wood mulch.
  • Maintain a layer of mulch around your tree. Do not mound the mulch around the trunk of the tree but lay a flat layer.
  • Make sure that water is not spraying the needles.
  • If the disease does occur, a copper fungicide can be applied once just before buds open in the spring (typically in mid-May) to protect needles from previous years and once after new needles have grown to their full length (in early to mid summer).
@sorce , should I just BURN IT?
View attachment 181799
Daconil is effective with multiple applications. The effectiveness will not be apparent right away. The plant is carrying the infection so the needles may still show symptoms as they develop. The litmus test is in the second year after repeated treatment. Funginal is also effective on red band needlecast.
I believe your pictures show primarily scale/ mite damage. Red band needlecast appears differently. I would reccomend dealing with that and work on strengthening the health of the tree at this point. The first thing i would check is the water retention level of the soil. Pines like dry feet. The extra humidity and moisture can foster more needlecast.
 

0soyoung

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I believe one should remove the affected needles as
  • Affected needles will never recover from the infection.
  • Affected needles are a spore source for continued infection.
Then spray (peroxide solution, Daconyl, etc.) to kill new spores.

If this is a continuing/common problem, application of a systemic fungicide may be necessary.
 

Clicio

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I believe one should remove the affected needles. Then spray (peroxide solution, Daconyl, etc.) to kill new spores.

Thanks, @0soyoung good to know.

Peroxide I have already sprayed, but this time I will take the affected needles beforehand.
If it continues I'll try Daconil also.
 

River's Edge

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I believe one should remove the affected needles as
  • Affected needles will never recover from the infection.
  • Affected needles are a spore source for continued infection.
Then spray (peroxide solution, Daconyl, etc.) to kill new spores.

If this is a continuing/common problem, application of a systemic fungicide may be necessary.
Both good additional points. I also prefer to use a staged approach with less serious treatments first, then only use stronger chemicals if needed. Not even sure if needlecast is present from the pictures provided. It is usually much easier to identify. I do not even note the paler bands that precede the darker red bands on the needles.
PS: I have added the hydrogen peroxide solution to my tool chest this spring. Along with Dish Soap, white vinegar, Neem Oil, Lime Sulphur, Malathion, Daconil, and a couple of systemic for heavy artillery.
 

sorce

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:):p:D

No Burny!

I would assume the pests are opening it up for the fungus.
Since the pests are simpler to control IMO.
Less guessing, just squishing!

All I know....

Is if I can't find a tree that will live without pesticides or fungicides. ....
Well no, I will find it....and if it's one species I can grow without worry. .than so be it !

Sorce
 

AJL

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From your latest photos Im still not convinced your tree has Dothistroma but is definitely infested with scale insect which can cause the patches of dieback along the needles where it feeds by sucking the sap.
The scales are protected by a waxy shell so spraying may not be 100% effective unless it incorporates a wetting agent eg soap or detergent. Removal of infested needles,squishing and thorough treatment with dish soap -detergent will kill most of them then and repeat in a few weeks to kill any larvae which emerge subsequently.
I have found inverting the tree in a bucket of soapy water for a few hours works well but it depends how big your tree is !!
It would be wise to keep the tree isolated from any other Pines in your collection.
 

Clicio

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I have found inverting the tree in a bucket of soapy water for a few hours works well but it depends how big your tree is !!

Thanks @AJL it's not so big and I like the idea. The tree is already isolated from the others and I will give it a good bubbly bath!
 

Clicio

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I believe your pictures show primarily scale/ mite damage. Red band needlecast appears differently. I would reccomend dealing with that and work on strengthening

Thanks a lot, I am now convinced it is scale, so I will do as told and treat this problem first (that seems to be the easiest part).
I'm trying to identify some mites also, but I am not positive so far.
As soon as the scale problem is solved, let's see if it has any fungal issues also.
Once more, thanks guys!
 

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