For the past couple of years, I've been trying to
deal with an oak wilt problem on my property in
Central Texas. At least weekly, I check the net for
information and am confused to say the least.

We've trenched deeply (52") and the line seems to be
holding, but within the trenched area are many trees that
I am fighting to preserve. (These trees are contemporaries
of Crockett and Travis and Bowie, so I owe them something.)
I macro-injected with Alamo where I could, but accessibility
to many of the trees implies microinjection, which brings
me to some questions.

Where is there any reliable information to be found
regarding micro- vs. macro-injection, especially regarding
Alamo? I've used tebuconazole, but where is any data
published about efficacy? How did they determine the dosage?

I am part of academia, so I am fully aware of the problems
arising from research funded by the 'researched.' I find
it curious that the Texas literature is completely silent,
as far as I can tell about alternatives to macro-injection of
propiconazole. Frankly, I need the information to do
a reasonable cost/benefit analysis given the limited funds
and time I have to invest.

Any help, especially from those not trying to sell me
snake oil, would be much appreciated.

Reply to post by Wilbon Davis, on September 07, 2001 at 23:31:45:

I think you know of me and what I've advocated insofar as chemical controls - but it's important to first concentrate on the research that somehow somewhere led to the suggestions that tebu or propoconazole be used as therapeutic. They are fungistats - sterol-inhibiting that only lead to the mutations that inhibit the ability to sexually reproduce. They do not stop the spread of wilt or keep a host from susceptible infection.
Further, levels determined for dosage rates reflect longevity and/or translocation of the infusions - how much before it's detected in trace levels at the furthest reaches of the host? In vitro, any molecular presence directly applied to mycelia will inhibit reproductive abilities - in nature, we need to be cautious due to the toxic effects of injection to the vascular tissue - ever see the stains on either side of injection sites? The chemical killed vital vascular cells - so how many injections would it take to kill the tree we're attempting to save?
Efficacy data - none exists. Statistical numbers are out there, we all hear them but the data to substantiate such claims must be under lock and key - like the trenching. Did you insert any type of semi-permanent barrier before back-filling the trenchlines? What is noted as a 74% overall effective barrier in root trenching is now down to 64% - is that a reflection of one more year of observation to a trench cut two years ago?
Nutritional compliments do exist but the simple and incorrect statements that "trees have no immune response" have people scratching their heads in confusion. I dare illustrate the reaction of the tobacco plant to aphids.
Phosphomide is one entry into your search that should yield some interesting results - Phythoptera and hypoxylon in addition to ceratocystis are problems we have on the Plateau now, where is the forest service when we need them for what they should be doing? Research uninhibited by chemical company dollars is the job of A&M and it's agencies but that's not going to happen. Until it does, you'll need to rely on your own quest for answers - I suggest UC Berkeley. Ask about their oaks.

Reed Holt