Ecological research backs fire mimicry approach

Science Daily is reporting on a new study that documents the importance of fire feedbacks in maintaining savanna woodlands. Fire feedbacks are the ecological basis for employing fire mimicry to restore the oak savannas here in California. While I don’t have much faith in the mathematical models that these scientists are using, it is interesting that they have come to the same conclusion I have reached based on my own, and others’, empirical studies.

From Science Daily (Oct. 29, 2009):

Trees Facilitate Wildfires As A Way To Protect Their Habitat

Fire is often thought of something that trees should be protected from, but a new study suggests that some trees may themselves contribute to the likelihood of wildfires in order to promote their own abundance at the expense of their competitors.

Upcoming workshop on tree and soil care at La Casa de Maria

THE HISTORY AND PRACTICE OF NATIVE TREE CARE

Saturday, October 10, from 9:30 am to 3:00 pm
La Casa de Maria Retreat Center, 800 El Bosque Road, Santa Barbara, CA

For thousands of years the native Chumash people tended the oak forests in the Santa Barbara. Now California’s oaks are endangered. Come for a workshop that will include presentations, time in La Casa’s oak woodland and a hands-on demonstration of tree care.

The Chumash used prescribed fire and other methods of traditional land management. To them, living on a living earth meant that the trees and forests were essentially organs of the planet. Keeping the trees healthy was fundamental for maintaining their quality of life.

Now-a-days, oaks and other trees are experiencing accelerated rates of decline in many parts of California, including the Santa Barbara area. A holistic view of the problem reveals that many of our aging trees and their soils are undergoing a major ecological shift brought on by changes in land management, especially fire suppression.

By revisiting the practices of the native people we are provided with an effective means of intervening in the decline of trees without the use of synthetic chemicals. Details will be presented on how fires and fire mimicry methods act to improve the fertility of soils and the health of trees. Results will be shown of case studies involving a suite of techniques to restore oak trees, including fire, mineral fertilizers, limewashing, brush clearing and mulching.

There will also be a presentation on the practical applications of the theories of agroecology that are now used in ornamental horticulture. By shifting from conventional techniques that utilize synthetic chemicals and pesticides to non-toxic organic products focused on improving soil fertility and insect ecology plant health is significantly improved.

This workshop will include a demonstration on traditional tree care using all-natural materials.

Lee Klinger, MA, PhD is an independent scientist and ecological consultant from Big Sur, with over 25 years of professional experience in the fields of biogeochemistry, forest ecology and soil science. He has held scholarly appointments at the University of Colorado, the University of Oxford, and the Chinese Academy of Sciences.

Corey Welles is the Plant Health Care Coordinator at Lotusland. He has seen dramatic improvements in the health of their plant collections since using agroecology based practices.

For more information and to register online go to: www.lacasademaria.org

More coast live oaks on the mend

Here’s further evidence that fire mimicry treatments are helping our diseased oaks. In 2005 I began treatment of two sick coast live oaks (Quercus agrifolia) growing in acidic soils in Mill Valley, CA. Each of the oaks had thin canopies and bleeding stem cankers. The owner informed me at the time that UC Berkeley scientists had confirmed the presence of Sudden Oak Death (Phytophthora ramorum) in trees on the property.

The photos below show how, after four years, the oaks have responded to fire mimicry treatments. The first photo shows a nice recovery of the leaf canopy, and the second photo shows how well the oaks are able to fend off the stem cankers. Bleeding is seen to have completely ceased in one of the oaks in less than four years!


UC scientists and other Sudden Oak Death researchers, those who truly want to help the oaks – we should be talking. Comments, at least?

Using fire mimicry to treat early leaf senescence in California buckeyes

The buckeye (Aesculus californica) is a deciduous tree, low and broad in stature, that is endemic to California. Every year these trees extend their gratitude by offering up a harvest of enormous size nuts. The species is a vital part of the California ecosystem and ever so worthy of our attention. Some even believe that tending the buckeyes is a responsibility passed on to us by the native people, who for the past few thousand years have been tending California’s buckeye groves.

Buckeyes do very well in open forests and savannas, especially in places where fires have been allowed to burn. However, on unburned lands buckeyes are often seen to be in poor health. Where forests are overgrown and acidified the buckeyes are experiencing serious health problems, including stem failure, canopy dieback, and any numbers of leaf blights including anthracnose and sudden oak death.

One of the first symptoms of ill health in buckeyes is the early seasonal onset of leaf senescence. Several years ago an astute friend of mine began noticing that for several years the buckeyes near her home had been losing their leaves earlier than usual. She contacted me about the problem and I suggested we try fire mimicry, the same treatments that I’ve been using on the oaks.

After four years of ongoing treatment here are the results . . .

Coast live oaks responding to fire mimicry

The use of repeat photography to document temporal changes in trees and landscapes was one of the many fine techniques I learned from my PhD advisor Prof. Tom Veblen. He taught me the importance of replicating details such the lens focal length, sky conditions, and time of day. My photos don’t always live up to his standards, but it’s not for lack of trying.

Today I would like to show repeat photographs for several coast live oak trees that have been undergoing fire mimicry treatments for exactly four years. Much of the credit for these results should go to Demetrios Sgouros, Leith Carstarphen, and Daniel Brooke who were among the first tree care specialists to recognize the utility of fire mimicry techniques in helping the many sick oaks here in California.

Fire mimicry effects on Douglas firs

As some of you may have observed, it’s not just the oaks that are suffering here in California. Problems are seen in the pines, the bay laurels, the sycamores, and the redwoods. Douglas firs are sick and dying in many places, especially towards the coast. Symptoms such as a thin canopy, a heavy cover of cryptogams (mosses and lichens), and bark deterioration are consistent with problems in soil fertility due to fire suppression and systemic acidification.

Fire mimicry methods were applied to these two sick Douglas fir trees in Woodside, California in May of 2007, with some additional work in 2008. Below are the photos showing the canopy changes after two years. Sorry, no control trees here, the owners rightly want to keep all their trees healthy.

On the origins of fire scars in California redwoods

Anyone who has spent time with the redwoods has no doubt seen and even ventured inside the giant trees with fire-scarred trunks. Certain trees are so severely scarred that you wonder how they are even able to stand. Some trees contain cavernous fire-carved rooms in their base with multiple entrances and even window-like openings. I’ve marveled at these trees and looked carefully at the orientations and shapes of their scars, and in doing so have found some odd things.

Having worked on fire lines in Alaska, Colorado, and California I’ve seen how fire scars are formed. A large quantity of fuel piled at the base of the tree is usually required to ignite a fire hot enough to penetrate the bark and scorch the cambium.

A characteristic burn pattern is seen on slopes where the vast majority of fire scars occur on the uphill face of the trunk (more than 90% in places)[1]. This is due to a couple of factors. First, hot air currents tend to drive ground fires upslope, especially during the day when fires burn hottest. (Keep in mind we’re talking about large ground fires, not large canopy fires which would more likely kill the tree.) The wind-driven fires tend to burn relatively quickly around the lower parts of the trunk, but eddy effects allow the fire to linger on the uphill side. Second, fallen leaves and branches tend to move downhill and accumulate on the uphill side of the trunk. Together these factors seem to account fairly well for the uphill side tendency of fire scars.

So imagine my confusion . . .