North American Fruit Explorers mailing list at ibiblio

[<dmnorton@royaloakfarmorchard.com>]

Betsy,

 

If there is bacterium within the canker, it will be dark in color, sometimes almost orangish brown, and you can see where it has effected the cambium tissue.  Cut out all of the dark cambium tissue until you see new cambium tissue that is unaffected.  It is best if you don't cut to the heartwood, but sometimes it may be necessary.  If you can get some Lac Balsam to coat the wound after cutting out the bacterium and them wrap the area with tree wrap, that would be best.  You can find Lac Balsam at http://www.treerx.com/ and Tree Wrap at  http://www.gemplers.com/product/G40503/TreeWrap.  Burlap tree wrap will also work.  These allow the wound to breath and dry out.  I have used black electrical tape for grafting and repairing splits in branches, but would not use it in this case because it does not allow the wound to breath as does the tree wrap.  Hope this helps!

 

Dennis Norton
Royal Oak Farm Orchard
http://www.royaloakfarmorchard.com
http://www.theorchardkeeper.blogspot.com
http://www.revivalhymn.com

----- Original Message -----

From: Hilborn.E@epamail.epa.gov

To: dmnorton@royaloakfarmorchard.com ; North American Fruit Explorers

Sent: Monday, December 24, 2007 9:42 AM

Subject: Re: [NAFEX] Fireblight lesions on trunk

Thanks Dennis! It sounds like there is hope for my trees!

 

How deep should I cut?  Just through the cambium to the surface of heartwood?

 

Also, I have done limited grafting, so do not have grafting tape.  Could I wrap the wounds with the black electrical tape that I have heard discussed on this forum?

 

Betsy

-----nafex-bounces@lists.ibiblio.org wrote: -----

To: "North American Fruit Explorers" <nafex@lists.ibiblio.org>
From: <dmnorton@royaloakfarmorchard.com>
Sent by: nafex-bounces@lists.ibiblio.org
Date: 12/22/2007 02:37PM
Subject: Re: [NAFEX] Fireblight lesions on trunk

Betsy,

Sometimes lesions on trees may not actually be fire blight but just a lesion
where it overwinters.  The bacterium spends the winter in these sunken
lesions (cankers) on the host tree. In the spring the bacteria ooze out of
the lesion or canker and that is how it gets spread.  In the past, I have
cut out these cankers on trunks by slicing the bark about 1 inch around the
cankers and removing it to clean wood.  I spray the area of "surgery" with
apple cider vinegar or a dilute mix of strep (Agri-Mycin) and seal it with
grafting tape or a tree wrap to protect the open wound.  The next growing
season I have had no blight reappear on the tree. I've done this on maybe 6
or 8 trees.  If more than one tree is affected, be sure to disinfect the
cutting tools between trees so as to not spread the overwintering bacterium.
Hope this helps!


Dennis Norton
Royal Oak Farm Orchard
http://www.royaloakfarmorchard.com
http://www.theorchardkeeper.blogspot.com
http://www.revivalhymn.com
----- Original Message -----
From: <Hilborn.E@epamail.epa.gov>
To: "North American Fruit Explorers" <nafex@lists.ibiblio.org>
Sent: Friday, December 21, 2007 9:57 AM
Subject: [NAFEX] Fireblight lesions on trunk


> My 3- 4 inch diameter oblique cordon apples have now shed most of their
> leaves and I am viewing the sad results of last spring's fireblight
> attack.
>
> Despite my ongoing efforts to prune out affected wood all spring/summer,
> I am seeing obvious lesions on the trunk of a few trees (3 of 11).
> Luckily they are above the graft. Unfortunately, they are low on the
> cordon - about 6-10 inches above the grafts.
>
> All of the trees have a lateral branch below the lesions. Most are weak,
> only pencil thick or so.
>
> Am I better off pruning that thick trunk to just above these weak
> laterals and trying to re-establish a leader, or am I just delaying the
> inevitable and putting my other trees at risk?
>
> Thanks for any advice you can provide.
>
> Happy Holidays everyone!
>
> Betsy Hilborn
> 7 (still) but surrounded by zone 8, NC
>