hereistay
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Is this pear fire blight?

According to you, the dried side under these cuts could be pear fire blight?
We are talking about asian pears.
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JONA
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Fire Blight would normally be very quick in showing itself on pears by blossom wilting and shoot ends and leaves dying back, especially young delicate growth.
The older wood is usually showing damage later.
The marks around those cuts looks more like very light die back.
The dead twigs could be just some die back through canker etc.
Just watch the foliage....if there is Blight ..they will show it.

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applestar
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I can't tell if that is fireblight, but very generally speaking, when you prune a pear tree, you don't want to see ANY brown-stained areas in the cut. If you do, sterilize the pruner blades -- I use alcohol in an atomizer spray, some people dip in 10%? chlorine bleach water. THEN cut several inches further down the same branch and check for any brown. Repeat, if necessary until you get to healthy, cream- colored cross-section with healthy green sub-bark layer.

Burn or securely bag and trash the affected branches.


...oooh Jona posted while I was composing my message... JONA, if you are still here, please check my content and point out if this is incorrect.

JONA
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Pruning advice spot on Applestar. Cant see the xylem on the cut but as you say , if it's brown stained then cut back until the staining disappears.

hereistay
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Thank you for your replies!
Applestar I use to use bleach and fire at every cut I make but the first cuts were made by the nursery man with no cleaned tools.

Jona I don't see any damage on young leaves and new shoots, only this brown marks.
Anyway I cut twice the first plant the first time I noticed these marks and I saw little black/brown spots on the cross section of the wood.
I think because of these spots, the nursery man told it could be a fungal disease.

JONA
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That could be canker hereistay.
You don't say how big your tree is, but I guess not too large. So...can you look over the surface of the wood further down the tree...especially the trunk area and around the graft union. If you find any wound or damaged area , this could be the source. Canker can be systemic and move up through a tree to appear anywhere.
I hope I'm just being ultra cautious though.!

hereistay
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I bought 3 young plants, 2 or 3 years from grafting.
A Hosui that I removed because too weak, a nijisseiki that I used as rootstock for niitaka (this one has no dieback or blackenings) and another nijisseiki.
On this one I noticed some damages and for caution I cut the damaged bark, put concentrated copper paste and mastic.
This plant showed again this mark on the top cut but seems to have stopped and seems to grow well.
Also around the treated bark there is no blackenings or brown marks.
The other pics are about a graft made with scions of the other nijisseiki (the one grafted with niitaka).
I cut once and put copper and mastic but after a couple of week this is the situation.
I knew that canker is a consequence of fungal disease or of fire blight,isn't it?
Anyway I give every 7 days bordeaux mixture against canker and fire blight and Tebuconazole after every heavy rain.

JONA
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Sounds like your doing all you can...so good luck with the trees.

hereistay
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I hope so Jona!
Anyway, today I noticed this blackening on the shoot of the graft with those marks, what can it be?
It is a confirmation that the brown marks under the cut are cankers?

Ps.: I read that it is possible to treat neonectria galligena by using carbendazim but this fungicide is forbidden in Italy (I think in whole EU). Another way is with high concentrated Tebuconazole and there is a mastic with Tebuconazole by a famous company. So I made a mixture with 10gr/lt if Tebuconazole with vinyl glue and put it on the marks.
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JONA
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As you say..carbendazim has been withdrawn from the end of Jan this year. Old stock can be used until the end of September.
I do think that may well be canker and you are doing all you can.
The trouble is that canker can travel through the tree... always upwards....via the trees own feeding routes. That brown staining just below the bark level when a shoot is cut is a sure sign.
Keep at it though.. luck may be with you!

hereistay
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I found other two pics of the first plant that the nursery sold me and than substituted.
This is what I ment with "brown spots on the cross section".
More and more convinced it is canker?
I don't really know if I have to eliminate immediately this plant to prevent contamination of other nearby asian pear plant or if I should wait to see what happens.
The plant is a Nijisseiki and had similar symptoms but the blackenning under the cut seems to have stopped.
When I first noticed the marks under the cut I cut away 3 points on its trunk that looked to be damaged, treated it with bordeaux mixture and covered with mastic.
The plant seems to grow weel unlike the Hosui that I definitely removed.
As soon as possible I'll post a pic of this plant.
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JONA
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Just keep an eye on the other trees, and as a precaution trim and paint any wounds that you see. That will stop any spore germination that could occur.

hereistay
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This is the situation now.
Ad you can see there are strange brown marks on the bark.
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JONA
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I would still carry on with your tree ...all the time the leaf is healthy there is hope!
Pears are tough.



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