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.

Sudden Oak Death researchers acknowledge fire suppression link to disease

24 04 2010

There is an exciting new video out titled – “The Teakettle Experiment: Fire and Forest Health” released by The Video Project.  A summary of the film states:

“The film documents the Teakettle Experiment, a ten-year collaboration of forest managers and scientists from diverse disciplines that investigated the effects of prescribed fire and forest thinning on restoring forest health.

A century of fire suppression has significantly changed many western forests, leaving them overcrowded and susceptible to disease, pests, and catastrophic crown fires that endanger lives and property.”

Here is the trailer (YouTube):

Besides describing the science behind the use of fire and fire mimicry practices in restoring forests, there is something else remarkable about this film. Read the rest of this entry »

Mimicking fire in western US forests

24 04 2010

There is an important book on fire mimicry that was written several years ago that I just came across.  The authors are Stephen Arno and Carl Fiedler, both well-known experts in forest management, and book is titled “Mimicking Nature’s Fire: Restoring Fire-prone Forests in the West” (2005) Island Press.

From the Introduction –

“After decades of studying western forests, the authors recognized that the magnificent old-growth trees that survived and depended on periodic fires disappear when deprived of this essential disturbance process. When forests of these venerable trees are managed using traditional timber harvesting methods, the features that made them famous ultimately disappear. When these forests are protected in ‘natural areas’ that fail to restore the historical role of fire – as in the majority of parks, wilderness, and primitive areas – the big old fire-resistant trees gradually die and are replaced by thickets of small trees. Our experience revealed that long-lived trees and other important features of fire-prone forests can be restored through management that mimics the effects of historical fires. Although research studies and practical examples indicate how to restore forests and reduce potential damage from wildfires, insects, and disease, they get little play in the media. However, it is these topics – scientific findings and real-world management examples – that we bring together in this book.” (my bold – lk)

Also from the Introduction –

“When people learn that more than one hundred million acres of fire-prone western (US) forests harbor deteriorating conditions outside of the historical range of variability, they are struck by the staggering extent of this problem. Given the difficulties of applying restoration, some may judge the situation hopeless. However, our experience suggests that any strategically located restoration treatments can produce noticeable benefits in reducing wildfire hazard to homes and communities and return important features of historical forests.”

Leave it to the experts to explain in abundant detail the critical reasons for implementation of fire mimicry practices to restore our oaks in California.

Grandfather oak

9 04 2010

Today my dear friend Donna Shoemaker, her friends Dick and Bob (real characters), Greg from Marin County Open Space (our helpful guide), and I ventured up King Mountain to do another fire mimicry treatment on an ancient coast live oak affectionately known as “grandfather oak”.

Donna, Dick, Bob, and grandfather oak (photo by Lee Klinger)

Read the rest of this entry »

An integral ecology of Sudden Oak Death

9 04 2010

Sudden Oak Death (photo by Lee Klinger)

Dr. Joel Kreisberg has recently published an excellent book entitled “An integral ecology of Sudden Oak Death: multiple perspectives of a forest pathology”.

The summary of the book states:

“The oak woodlands of central and northern California have seen a rapid decline of native oak trees in the last ten years attributed to Sudden Oak Death (SOD). Phytophthora ramorum has been isolated as the forest pathogen focusing the academic and public research agenda. Integral Ecology offers a systematic approach as a means of balancing multiple perspectives. Science is seldom value free and offers more then one conclusion. Alternatively Sudden Oak Death is a response to a larger set of variables including shifting climate, general forest decline and the ongoing impact from human activities. For an integral ecology all parties may be partially correct–the difference is in perspective. The interpretation of Sudden Oak Death as P. ramorum encourages institutions to combat the disease using technology and research as its primary tool. SOD as forest decline offers a choice to either deny our role in these changes or to learn and adapt with it. In this capacity, nature is the teacher and we are the students.”

About the author – Dr. Joel Kreisberg, DC, MA is the Founder and Executive Director of the Teleosis Institute, dedicated to reducing healthcare’s footprint while broadening its ecological vision. Dr. Kreisberg is currently an adjunct professor at the School of Holistic Studies at John F. Kennedy University in Pleasant Hill, CA. Read the rest of this entry »

Acid rain in Big Sur – March 2010 update

7 04 2010

Another acid rainbow in Big Sur (photo by Lee Klinger)

Below are the rainfall amounts and pH results from Big Sur for March 2010. With the notable exception of one rainfall event on the 9th, the pH values in March were a bit lower (more acidic) than average over the past four years (see here, here, here, and here).

Rainfall amounts and pH in Big Sur - March 2010

Fire mimicry 2-year results with coast live oaks

7 04 2010

Yesterday I re-photographed several coast live oaks in Santa Barbara that have been undergoing fire mimicry treatments for two years. Here are the results. Note that the latest photos were taken a few weeks later in the season than the original photos. This will have some affect on the results due to the few weeks of additional growth. However, the examination of a control (untreated) oak here indicates that this additional growth cannot explain the significant increase in canopy health seen in the results with the many treated oaks. Read the rest of this entry »