Is this fire blights?

Just discover this on one of my pear trees. There are 4-5 spots like this. Is this fire blight?
If it is, what am I suppose to do besides cut off the affected branches.

We had a very wet spring, it rained or drizzled days on end. But I have another pear tree nearby, everything looks normal.

Yup it is. Prune out all of the affected branches to a 6 or so inches from the blackened area. Double check that the cut area is green and healthy.

For prevention, people here use Kocide 3000 or antibiotics (?). I don’t.

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I don’t know what the concensus in sterilizing tools is, but I like to spray my nippers and the cut with rubbing alcohol, dilute bleach, or Pine-sol type stuff at each cut. Bag the waste at once. I think some people cauterize the cut with a little scorch from a propane torch.

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What kind of pear tree is it? I agree it is fire blight.

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Alcohol is a good solvent but not that good at killing bacteria. It eventually does but requires 10min or more. Chlorine bleach is great at killing stuff, but erodes your tools. Many opt for using Alcohol, but you need to wipe with it, not just soak it or give it a quick spray.

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True. I’ve got pinesol now, but haven’t had to use it yet. Alcohol seems to have worked for me in the past, though. And I have used dilute chlorine bleach and then just cleaned everything up, but it can be a pain for just a few cuts.

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@Sara_in_philly
I agree it is fireblight but before you break off the branches and I do mean break let me give some advice 1. Burn the infected areas in the barbecue grill. It’s a susceptible variety so break that tip off with your hand ASAP at least 6 inches to 1 foot below the strike and consider where it is infected ( likely the fireblight bacteria entered through the bloom a few weeks ago) . 2. Don’t use your pruners use your hand because if that bacteria transfers your spreading the disease. 3. Keep a close eye on your fruitlets because chances are the same pollinators visited many blooms with the Fireblight bacteria on them. That fireblight goes after growing tissue only so blooms and new tip growth are the biggest sources of infection right now. If you see new blooms especially on the trunk pluck them off ASAP. Some trees rebloom. Losing branches and fruit is no big deal long term but do not let it enter the trunk as it will kill your tree. We have all seen fireblight come and go with some years being worse than others. Copper is a bacteria inhibitor so when people say spray kocide they mean because it’s copper which inhibits bacteria prior to bloom next year. This year spraying copper will do little good because the fireblight was infecting those fruitlets and branch tips weeks ago. I’m just reiterating the good advice everyone else has already given you! Most infection occurs at 65 degrees / 65% humidity Pear tree Fireblight research so you dont have to - #38 by clarkinks. Next year just remember bees start flying at 50 degrees and they and other insects transfer the illness when pollinating. The branch tips may have been infected with FB by birds feet or insects eating an infected tree and then flying to yours.

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Clark, I had never heard that about breaking branches- thanks for a great tip. How big a branch are you thinking of when you say that?

Thanks!

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@marknmt
No more than an inch or so diameter branches break off easily. Even big ones I break off and clean up later with a saw if I see no more infection. If your using pruners the bad thing is to disinfect them takes alcohol or bleach which is not overly good for the pruners and usually people dip between cuts which sometimes leaves fireblight on the pruners reinfecting the tree they are trying to save in a lower spot than the infection was previously. As we are all to painfully aware at times pear branches break off easily.

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Thank you for your quick reply, everyone! @bleedingdirt,@marknmt, @Steve333,@growjimgrow, @clarkinks

I was busy yesterday afternoon. So the first chance I got after everyone confirmed it’s fire blight, I went out prune off the affected branches.

This is what I did: I found a really old pruner and dipped it into 30% diluted bleach (30% Clorox bleach, 70% water) after each cut. Most of time I pruned off more than 1 foot from the blacken area. I double bagged the diseased branches with trash bag, they are in the garbage pick up truck somewhere now.

Now I can only hope this is good enough.

While hubby and I were pruning, I realized there were a lot more affected branches than the 4-5 branches I originally thought. Don’t know why I didn’t notice them sooner. Now most of fruitlets are gone, and the tree is a lot shorter.:fearful:

@clarkinks I already pruned off the branches when I saw your post about break it off instead :sob: Do you think I should go back try to break them again? Thank you for explaining how a tree get affected by the bacteria, I was wondering about that. So, if pollinators carried the disease over, there is no real way to prevent it, is there?

Just some background info: I have 2 pear trees, they were all impulse buys from big box stores 4-5 years ago. One for $5, the other $7. I just started getting into graft then, everything was a potential root stock to me😀

One tree is Ayer, and I promptly lost the tag of the other, i.e. the inflicted one. (@growjimgrow I hope this answer your question, I don’t know what it is🙂) All I know is it’s one of the popular one that suppose to cross pollinate with Ayer.

But it turns out the unknown one always flowers one week after Ayer! Since there is no pear tree nearby, every year I have to pick some flowering pear tree flower to pollinate Them by hand. If this is not bad enough, by the time the unknown tree begin to flower, most of flowering pear tree are done flowering!

I have grafted a few other pear on to these two trees a couple of years ago, hopping they can cross pollinate. So far the grafted pear branches have grown very tall, but no flower yet.

Both trees started fruiting last year, the Ayer pear was very very good! The unknow tree was not as good. It has smallish yellow pear, someone said it may be kieffer.

All my fruit trees get sprayed with copper, captan and triazicide with spreader at peach bud break, pear trees bud break is much later than the peach. So the pear trees get copper once a year before its bud break, it doesn’t seem to be enough to prevent fire blight on this tree. but, we had a very wet spring.

And whenever peach get sprayed for brown rot and bugs(captan and triazicide), I also spray the pear for good measure :grinning:

So this is all the background and my practice about my pear trees, do you see anything wrong? Anything I can improve on?

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I break. Much easier. I think breaking also helps indicate uninfected wood from infected. My opinion is that clean wood snaps off easier.

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@Sara_in_philly
The way you handled it sounds fine to me and nothing further is needed. I would next year top work that tree over to resistant varieties like Tyson, warren, Potomac, Harrow delight etc. . You might go without pears two years but the harrow delight will start producing in 2 years after you top work and it does not get fireblight as bad. It has similar resistance to Ayers.
@Auburn
I agree diseased nutrient deficient wood is very different than good wood.

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Reading all these threads about fire light has made me paranoid.

This past weekend I pruned out all the blossoms on my young trees, entering their third growing season to preserve vigor. Was very concerned about fb…

Here is the protocol I used. Interested in folks’ opinions:

I started cutting blossoms on each branch closer to the trunk, and worked my way out towards the tip. The logic being that if fb bacterium had entered those blossoms closer to the trunk, the branch further out would be hosed anyway; however the reverse wouldn’t necessarily be true, and cutting in the reverse order could potentially spread the infection inward.

I used two pruners, and switched them for each branch, soaking in rubbing alcohol in between branches. Same logic as above applied…

I haven’t been hit yet, but am very wary!!!

Thanks to @clarkinks for all the wisdom you share on this site!!! I always appreciate your posts and am sorry you get hit by fab so hard…

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Just want to give an update on the fire blight of my pear tree: so far so good!

After I pruned off the affected branches on the first day, I have kept an eye on the tree. I had to broke off couple of smaller branches a couple of days later, then no more blacken tips.

I will keep monitoring the tree, hope the tree will be ok.

Thanks everyone for your help!

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Glad you got through it. I’m fighting all kinds of diseases on my trees too. I think this rainy weather, as much as plants like it, is a disaster.

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On a trip for 3 days and came home to this on a pluot tree. I don’t know if it is fire blight. An entire 6 inch diameter branch is dead.


Not fireblight, which to my knowledge does not affect stone fruit.

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@marknmt

That is true fireblight doesn’t impact any stone fruit. Borers, canker etc. Do impact stone fruits.

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@marknmt , @clarkinks thanks for the info. The large branch I cut has rotted heartwood where it attaches to the trunk so I may lose the whole tree.

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