Video recording of “Forest restoration theory and practice based on Indigenous cultural tending”

17 11 2020

Here a Youtube video of my recent lecture and discussion in the course FORESTS, hosted by the Humanities Center of Texas Tech University. Many thanks to Bruce Clarke and Michael Borshuk for facilitating this talk!


Sudden Oak Life workshop at Sienna Ranch on Oct. 23

28 09 2011

Sienna Ranch, Lafayette, CA

Sudden Oak Life Workshop

Date: Sunday, October 23, 2011

Times: 11:30 am to 12:30 pm (free), 1 to 4 pm ($40)

Location: Sienna Ranch, 3232 Deer Hill Rd., Lafayette, CA

Contact: Lindsay Daley (707-889-3744)

Learn how to improve and restore the health of the oak ecosystem in this enlivening workshop with “Sudden Oak Life” oak tree expert and scientist, Dr. Lee Klinger.

For thousands of years the native California people tended oak forests and other food-producing ecosystems using prescribed fire and other methods of traditional land management. Now-a-days, with the suppression of fires, oaks and other trees are experiencing accelerated rates of decline in many parts of California, as witnessed by spread of epidemics such as sudden oak death.

Join Dr. Klinger as he demonstrates various “fire mimicry” methods to help the oak ecosystem flourish. Demonstrations will include a variety of practical, hands-on techniques, and we will treat several grandmother valley and live oaks on the ranch. All treatment methods are organic, and no synthetic chemicals are used. Details will be presented on how fires and fire mimicry methods act to improve the fertility of soils and the health of trees, and results will be shown of case studies involving a suite of techniques and natural products to restore oak trees.

Lee Klinger, MA PhD is an independent scientist and ecological consultant from Big Sur, CA with over 25 years of professional experience and over 50 peer-reviewed publications in the fields of biogeochemistry, forest ecology, and soil science. Dr. Klinger has worked as a staff scientist at the National Center for Atmospheric Research in Boulder, and has held scholarly appointments at the University of Colorado, the University of Oxford, and the Chinese Academy of Sciences.

Message from an arborist

13 01 2011

Yesterday I received this email from Don Cox, an arborist who has been involved with the Sudden Oak Death problem since the very beginning. He has agreed to let me post it here:

Dear Dr. Klinger,

As a California arborist involved with the “Sudden Oak Death” syndrome since 1995, I have been aware of your work in this area. I know you are on the right track with ‘Sudden Oak Life’ and mineralization of the soils.

Since the 1990’s even before we had a positive ID of P. ramorum as a primary factor in SOD and the emphasis was directed on the pathogen as the primary cause, I believed that there was a complex set of circumstances for the advance of this species decline. I saved some significant trees for my clients in the midst of SOD killing fields of Marin, Sonoma and Santa Cruz counties, with a comprehensive PHC (plant health care) approach including soil re-mineralization. I see that you have taken up this comprehensive approach with soil health as the focus and you have had the determination to stick with your convictions in spite of the opposition.

I’ve been reviewing the Sudden Oak Life website and the results you are getting with your tree care programs; you have a lot of good information there. Keep up the good work.

Don Cox

ISA Certified Arborist WE-3023A, Tree Maintenance and Plant Health Care Advisor

Don has pointed me to two important websites: – which has a wealth of information on the use of minerals to improve plant health and soil fertility – with information and services on health care for trees of the Central Coast of California

Thank you Don for your support of a broader, more ecological approach in addressing Sudden Oak Death.

Oak health workshops at Hidden Villa

31 12 2010

In late January I will be giving two workshops on oak health at Hidden Villa, an educational wilderness preserve in Los Altos Hills, CA. The workshop on January 27 (Thursday) will be tailored for tree and land care professionals, and the workshop on January 29 (Saturday) will be for the public. Please see the flyer below for full details. Information can also be found on the Hidden Villa website calendar page. Feel free to leave a comment below if you have any questions for me directly, or email me (see Contacts page).

Sea shells to help sick pine trees

11 08 2010

Sea shells to make soil fertilizers for sick trees

From the Daily Yomiuri Online (h/t Ralph):

Scallop shells may help save pine trees

The Yomiuri Shimbun

A fishing town in northeastern Miyagi Prefecture has turned to the lowly scallop to save its pine trees from a weevil blight.

Minami-Sanrikucho is experimentally grinding the shells of scallops, the town’s speciality, into nutrient-rich powdered fertilizer that it hopes will make the pines resistant to weevils.

The town has about 1,924 hectares of pine woods, but since around 1970 weevils have been badly damaging the trees, mainly in a coastal area of the town. About 20,000 damaged trees have been cut down.

Local residents fear not only that the blight may ruin one of the town’s scenic attractions, but that loss of the trees may result in landslides. Pine trees also absorb carbon dioxide, thus helping reduce global warming.

Since the blight began, the town office has spent about 10 million yen a year on such measures as spraying pesticide and cutting down withered trees, to little effect.

A town official heard that another municipality suffering from the same problem had found it effective to spread oyster shells as fertilizer on the soil in pine woods. Calcium and minerals contained in the shells promoted growth of the trees and made them strong enough to withstand the weevils.

Scallops are farmed in Minami-Sanrikucho, producing from three to five tons of shells that are thrown out every day. A marine products processing company in the town developed a technology to grind the shells into powder.

As powder made from scallop shells is finer than that from oyster shells, it can more easily permeate soil. Also, as the powder contains strongly alkaline calcium, it is expected to more effectively protect pine trees against the weevils.

On July 7, the town started the experiment using the new fertilizer. Town officials and local residents spread a total of 60 kilograms of the fertilizer around 22 dying red pine trees that are 57 years old. The town will check the condition of these trees every three months and spend two years monitoring the fertilizer’s effectiveness.

“I hope the pine woods will be revived and help curb global warming,” a 74-year-old resident in the town who helped spread the fertilizer said.

(Aug. 11, 2010)

Soil minerals stimulate olive trees

27 07 2010

Today I received an interesting email from Chuck Cunningham, a tree grower in Buellton, CA who has taken a keen interest in the work I am doing. He writes:

I forgot to mention an unusual occurrence in my “fruitless” olive trees.  I have been tending and growing some 40-50 Olea Europae “low fruiting” olives that for the last several years have only developed perhaps 6 olives grand total. After using Azomite on the trees they are all fruiting? I am not sure if they will hold, but it is interesting since to my knowledge nothing else has changed.

Over the years I’ve seen a number of cases where stressed, poorly-producing olive trees have responded nicely to topical treatments with soil minerals. I am aware of several olive growers who are improving their yields significantly by amending soils with alkaline-rich minerals, which improve soil fertility and, thus, tree health and productivity. The soil minerals that I use in my practice are a combination of finely-ground Azomite and calcitic limestone. Azomite is a volcanic ash that is loaded in trace minerals. The calcitic limestone helps to buffer soil acidity and provide calcium, a major constituent of bark and wood.

Acute Oak Decline in the UK – Part 2

30 04 2010

In my previous post on Acute Oak Decline I posed the question of whether ecological factors are predisposing oaks to this “new” disease. My concern is that research groups led by the plant pathologists will remain focused on the disease model and not consider the ecology of the problem. I encourage scientists studying Acute Oak Decline to pause for a moment, take a breath, and consider things like rain pH, soil fertility, and ecosystem structure before launching into a costly vortex of biological studies on whatever bacterial species is determined to be the “cause”.

In this post I would like to present some preliminary findings of soil fertility in a stand of diseased and non-diseased English oaks (Quercus robur) in Bushy Park, London, UK. Several oaks showed bleeding symptoms characteristic of Acute Oak Decline (see photos below), although the bacterial species was not positively ID’d.

English oak with Acute Oak Decline in Bushy Park, London (photo by Lee Klinger)

Closeup view of Acute Oak Decline bleeding symptoms. Note deep cracks in the bark. (photo by Lee Klinger)

Upon inspecting the soils I noticed that near the diseased trees there were large mats of mosses, whereas few mosses were found around the non-diseased oaks. Having a strong interest in the influence that mosses may have on soil fertility, and thus oak health, I, along with Neville Fay of Treework Environmental Practice and Vinodh Krishnamurthy of Soil Foodweb Lab Services and Research, devised a simple test. Read the rest of this entry »

Acute Oak Decline in the UK – Part 1

29 04 2010

Acute Oak Decline (photo from BBC)

Yesterday the BBC ran a story on Acute Oak Decline in the UK titled “Oak disease threatens landscape”. The lead in to the article states –

“The continuing spread of a deadly disease that affects the UK’s native oak trees is causing concern among tree professionals and conservation groups.”

The article goes on to describe the problem as Acute Oak Decline (AOD), which is caused by a bacterial infection that can “kill an infected tree in just a few years.”

Further down in the article is the following alarm –

“I have never seen anything like it,” said Peter Goodwin, co-founder of Woodland Heritage.

“Its spread over the last two years has been quite alarming.”

And –

“We’ve never had a bacterium that is capable of doing what this one is doing.”

In the words of Yogi Bera, “It’s like deja vu all over again”.

When similar alarms were being raised about Sudden Oak Death in the early 2000’s, the plant pathologists were able to muster up many millions of dollars in taxpayer money all to study a single disease-causing organism, Phytophthora ramorum. If you didn’t buy into their disease model then you simply didn’t get funded. Believe me, I tried – three times.

My concern with the hype around Sudden Oak Death, as it is with Acute Oak Decline, is that the role of ecology in predisposing oaks to disease is not being adequately addressed.

In the case of Acute Oak Decline, I suspect that there may be problems with the fertility of the soils that are predisposing the oaks to infection. Given the good results we’re getting here in California by adding mineral fertilizers to soils around oaks infected with Sudden Oak Death, it would be wise for the scientists studying Acute Oak Decline to pay close attention to the soil ecology.

In Part 2 of this post I will present and discuss some soil chemistry results obtained in February 2009 from an area around English oaks with Acute Oak Decline in the Royal Parks of London.

Forest vegetation and soil succession

25 12 2009

Readers who are interested in more details of the general theory and empirical studies of forest decline and soil acidification please consult this paper:

Forest vegetation and soil succession

by Lee Klinger MA PhD

Presented at: Treework Environmental Practice Seminar XIII
Linnean Society, Burlington House, London, UK – 30th June 2009


Forest communities are complex systems comprised of populations of organisms representing every kingdom of life – plants, animals, fungi, protists, and monists – living and growing together on the land. They are part of a larger group of communities that constitute the regional ecosystem, or landscape. Forest communities are developmentally related to the surrounding communities in ways that can be characterized through chronosequence studies. Chronosequences from southeast Alaska and subarctic Canada are described and interpreted as indicating that, while early successional processes facilitate forest growth and productivity, later successional processes tend to slow and inhibit forest growth and regeneration. In many places forests are seen to have transitioned into peat bogs over the course of several thousand years. This is thought to reflect the true climax nature of bog ecosystems.

Forest to bog transitions are linked to two main developmental processes: podzolization and paludification. Podzolization affects many northern forests and involves the translocation of iron, aluminium, clays and organic compounds in response to vegetation, especially mosses, acidifying and leaching the soils. This is often followed by paludification, which occurs as peat-forming mosses, such as Sphagnum species, become established and expand.

From the perspective of succession, forests are seen to flourish under early successional conditions, conditions that are enhanced by periodic or regular disturbances. However, where disturbances are eliminated, forests begin to show decline as a consequence of natural successional changes. This work points to the potential for managing forest ecosystems through the maintenance of disturbance regimes and the remediation of acidification tendencies in the vegetation and soils.

Download the complete paper here.

A holistic approach to mitigating pathogenic effects on trees

25 12 2009

For those of you who would like to read more about the details of the science and techniques involved in fire mimicry practices for oak restoration, here is a paper I wrote last year:

A holistic approach to mitigating pathogenic effects on trees

by Lee Klinger MA PhD

Presented at: Treework Environmental Practice Seminar XII
National Museum Cardiff, Cardiff, UK – 13th November 2008


The conventional ‘disease model’ approach to tree health focuses on identifying and controlling a specific pathogen (or pest) implicated as the causal agent of tree decline. Alternatively there are more holistic approaches in tree health that address a broader suite of processes occurring at the ecosystem level which may be predisposing the trees to infection by disease. Here I describe a holistic methodology that takes into account not only the proximal agents involved in tree decline, but also the age and structure of the forest, the abundance of cryptogams, the fire history, the acidity of the precipitation, the fertility of the soil, and the historical land care practices. This methodology is being implemented in the oak forests of coastal California which are experiencing high levels of mortality attributed, by most scientists, to the pathogen Phytophthora ramorum (aka sudden oak death). Evidence reported here of 1) acid rain, 2) acidifying effects of mosses and lichens, 3) the presence of acidic and nutrient deficient soils, and 4) a much lowered incidence of disease in recently burned areas, points to the likelihood that fire suppression has radically altered the structure and successional status of the forests, leading to enhanced competition and systemic acidification. Case study results of sick and diseased coast live oaks receiving holistic care, aimed not at treating P. ramorum but at reducing the environmental acidity, fertilizing the soils, and otherwise mimicking the effects of fire, show noticeable improvement in the health of the oaks after one year (78%, n=152), with further improvement in years two (84%, n=134) and three+ (81%, n=80). While the results do not indicate that the incidence of P. ramorum has changed significantly in the population of treated oaks, there is evidence that the sick, non-diseased trees are better able to resist infection.

Download the complete paper here.