thanks jp and frax. jo, where is the origin of the infection?
amazing how almost all the response so far is about the torch. this is old school effective--the tubes either wound or clog or get overgrown. heres chat w a brit
Have you carried out the cauterising many times?
&yes typically now on lesions. just a quick double pass for dry cankers, and just enough to stop the sizzling on the juicy bits. seen it done in orchards in NZ, and WI and MI and FL in the US.
note in the easytofind lit below they talk about scorching the wood, but as you note this damage can predispose to infection. at the most i watch the wood darken but not shrivel or crack. it depends on how degraded the tissue is--careful tracing essential ahead of torching, so the flame can keep moving.
Has there ever been any anecdotal evidence of associated fungal activity where the burning has occured.
&one patch of oyster fungus.
I often see the likes of Bjerkendra on burnt oaks which I imagine is partly due to dead material but also perhaps the change in bark chemistry?
&Wood chemistry too. bad to boil the juice out of wood generally, but when some/much of that juice is infected/infectious it's a hard call. i try to err on the side of missing some; there is usually a followup eruption or two to deal with anyway.
Would a moving of the first line of car parking away from the outer periphery of RPA & an amelioration of the root zone be a worthwhile consideration with this post oak?
& Cars are way beyond dripline, and one is afoul of town planners etc if one takes parking away; my god man this is america; cars are mobile sanctuaries and objects of worship!
soil amelioration (my favorite word as it derives as my surname) is focused on the symptomatic sides of the rootzone; toward the sidewalk mainly. Companion plants are being reviewed now; a mix of grasses and perennial flowers maybe ground orchids and asarum.
http://whatcom.wsu.edu/mgtemp/classe...ase/EB1013.pdf
Burning cankers to cauterize them
is a method which comes from New
Zealand. Tree fruit owners use a
propane torch to cauterize cankers on
the trunk and larger branches. They
direct flames on the canker until the
underlying tissue begins to crackle
and char (5 to 20 seconds). *Ed note--Yikes!* Treatment
must extend to the outer canker
margins, where active bacterial
infection occurs. Treated cankers are
inspected in 15 to 20 days. Cankers
should be heated again if the
disease continues to show activity
beyond the burnt area. Cauterizing
should take
place in early spring, before bloom,
when the bacteria are active, and
the cankers are enlarging. Cankers
observed in the fall should be
cauterized immediately to prevent
spread of the disease during cool,
rainy fall and winter weather.
Several months following treatment,
charred tissue will slough off, leaving
a well-formed callus.
and from
http://www.extension.uidaho.edu/nurs...it%20Trees.pdf
There is no complete control by
any single method for bacterial canker and gummosis of stone fruit trees but
there are many useful practices that can help reduce the risk of infestation. ...
Cankers can be controlled by cauterization with a hand help propane burner in
early to mid spring. Hold the flame up to the canker for fifteen to twenty seconds
until the bark and underlying tissue begins to crackle and crinkle.
*That's more like it, still leaving juice in the wood.*
If it is
necessary you can repeat this method in 2-3 weeks (Agrios, 445). ...
Works cited
Agrios, G.N. (1997). Plant Pathology. 4th Ed., Academic Press, San Diego, CA
