California Agriculture paper on Sudden Oak Death: Can conclusions of treatment efficacy be made in trials where n = 5?

27 05 2009

Earlier this year pathologists M. Garbelotto and D. Schmidt from the University of California at Berkeley published a paper in California Agriculture (a journal published by the University of California) in which they claim to have tested my holistic methods, and found that the application of “azomite soil amendment and bark lime wash was always ineffective, and did not reduce either growth or infection rates” of Phytophthora ramorum. Conversely, they report that “phosphonate treatments, legally registered in California to control sudden oak death, were effective in slowing both infection and growth rates”. They pretty much make it seem like it’s an open and shut case. But wait, there’s more.

Venturing into territory I’ve never seen touched in a research paper before, the authors then pass judgment on the aesthetic nature and even the legality of my methods. Here is what they say:

“Besides this lack of efficacy, we found that the sheer amount of material needed to treat each tree with azomite and lime wash was cumbersome and aesthetically unpleasant due to the large amounts of azomite on the ground around treated trees. Although this treatment is being touted as a holistic fertilizing approach aimed at enhancing the overall health of the tree, it is often and illegally prescribed to directly control sudden oak death. While true fertilization treatments do not require a registration, those used to directly control a disease do; as such, the azomite and lime wash treatments appear to be in a legal “grey zone.””

Sounds more like an indictment than a study of my methods.

So I have just one question, who of you reading this feel such claims can be justified based on a field study of just five trees? Yep, you heard me correct, just five trees!

I’m sorry, I actually have a whole lot of questions.

I state explicitly that my toxin-free holistic approach is not intended to be fungicidal in nature, so why was it tested as a fungicide, against a toxic fungicide?

Given that I developed the holistic methods involving AZOMITE® and lime wash, why was I not consulted on this study? How can I be certain that my methods were implemented properly? Were the trees cleared of brush and the trunks powerwashed to remove mosses and lichens? Did any buried root crowns get excavated? What were the application rates? Were the applications repeated (as recommended)? Was organic compost and/or mulch added? (The methods reported in the paper indicate that the answers are “no” to most of these questions.)

My methods are recommended to be used over a period of at least three years. Why was the study terminated at 18 months?

Where exactly are the experimental trees? How were they selected? What was done to guard against investigator bias? What information was recorded for each tree? Was any information collected on the soils? Can the trees be visited and inspected?

Readers should keep in mind that the tests in the field study are on the susceptibility of branches to SOD infection, when in fact the SOD infections are rarely in the branches of coast live oaks. Rather the infections occur mainly in the lower trunks and root crowns.

I consider as nonsense the claims of inefficacy and illegality of my holistic methodology, and unless the above questions can be properly addressed, the claims will remain as nonsense. Based on their reported methods and sample sizes it can already be said that the authors did not fairly test the holistic methodology. I honestly can’t believe how this paper made it through peer-review. Maybe they should have asked me to review the paper ☺. Despite the improbability, it really would have been the most professional thing to do.

For folks that are interested in seeing results on the efficacy of holistic methods involving a more respectable sample size (150+ trees), please look at my recent paper available online here.

One last point – I’ll leave it to the readers to decide on the aesthetics of the two methods. These are two photos of the different methods published with the article. The toxic phosphonate treatment is on the left, the holistic (partial) treatment is on the right. Some folks do find the white trunks unappealing, which is why we sometimes apply a tint that can mask the white. Also, note the healthy canopy of the tree on the right.

Aesthetics of phosphonate (left) vs mineral (right) treatments

Aesthetics of phosphonate (left) vs mineral (right) treatments



5 responses

28 05 2009
Jim Mather

Absolutely incredible. Five replications? FIVE?? Perhaps we should send the “scientists” who did this study at UC back to elementary statistics class. On second thought, skip that; I’ll just quote them the basics of the importance of doing many replications (well beyond 5) from a source as widely available as wikipedia: “In engineering, science, and statistics, replication is the repetition of an experimental condition so that the variability associated with the phenomenon can be estimated. ASTM, in standard E1847, defines replication as “the repetition of the set of all the treatment combinations to be compared in an experiment. Each of the repetitions is called a replicate.”

Also, perhaps the UC people need to go back to school to understand an even more basic concept in science — falsifiability. “Falsifiability is the logical possibility that an assertion can be shown false by an observation or a physical experiment. That something is “falsifiable” does not mean it is false; rather, that if it is false, then this can be shown by observation or experiment.” This UC paper seems more written as an attempt to bad mouth an approach that they don’t like, rather than being open for peer review and criticism from anyone (saying that Klinger’s approach was like using orange juice? Are they seroius??).

And these UC people were concerned whether the tree look pretty or not? I’m incredulous.

Also incredible was that they kept referring to AZOMITE® as “azomite” as if it was a generic product. Huh?? Do they not know the intricacies of using

It seems to me that the UC “researchers” have some ax to grind with holistic approaches and AZOMITE® specifically. However, even a freshman taking his first science class in college should be able to tell you that there is only one standard to evaluate the efficacy of any approach, regardless of the scientist’s judgment that some approach may be “alternative” or questionable; that standard is the Scientific Method. Sadly, the UC people seem to have resorted to the very pseudoscience that they seem to want to decry.

31 05 2009

I would like to clarify several mis-statements that have been made on this site:
1. Phosphonates(Potassium Phosphite or Agrifos) is NOT a toxic fungicide. It is a actually a low toxicity fertilizer that has been registered as a fungicide. It is less toxic than table salt.

2. Phosphonates do not kill anything , but rather boost the Immune systems of trees so that they can compartmentalize SOD cankers and help trees resist infection. They also benefit trees in numerous ways. They are very effective.
If anyone has trees that have been affected by SOD, they are best treated early with the agrifos product mixed with pentrabark as a basal spray. These are NOT toxic pesticides but low-risk and low toxicity products and are proven to be effective through many scientific trials.

REPLY – If people want information on Agri-fos then this is not the site for them. There’s plenty of places to go if you want to use Agri-fos on your trees. Agri-fos IS toxic. I’ve frequently observed that where ever Agr-fos is sprayed onto an oak tree all the green plants, the mosses, lichens, ferns, grasses, etc. die. Agri-fos may not be too toxic for you but it is too toxic for me and many other people who come to this site to find out about alternative, non-toxic methods of tree care.

I do invite you to share experiences on any toxin-free ways of caring for trees that you have found useful.

1 08 2009

Do you know of a good tree DR near south western riverside county CA I have some oak trees that look sick to me. I live near the Santa Rosa Plateau and I have several differant types of oak trees on my property.

John Gammon

1 08 2009
Lee Klinger

Thank you for your comment. Please check your email.

10 11 2013
Damien McAnany

I think an even more critical failing of the experiment is that after the AZOMITE® and lime wash were applied, the branches in the canopy that were selected were CUT OPEN and then exposed to the SOD pathogen. If the remineralization assists the tree in keeping out SOD because of strengthening the bark, then cutting bark open will certainly not disprove the efficacy of the treatment.

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