A single fire mimicry treatment is not effective for longterm oak recovery

I recently inspected a grove of oaks that I treated with fire mimicry methods four years ago. Two of these oaks have stem canker infections, possibly Sudden Oak Death, that were present before the oaks were treated. As the photo sets show, the oaks responded dramatically after only one year. The property owners, pleased with the results, opted to not continue treatments of their oaks despite my recommendation that the oaks receive at least three annual treatments. While some of the oaks are still showing improvement four years after the 2012 treatment, these photos demonstrate that the oaks have undergone a clear decrease in canopy density after the initial response. I believe this decline is because they did not receive followup treatments.

Consider the huge volume of soil encompassed by the roots of an oak tree. These soils have been undergoing nutrient depletion for however long its been since a fire last burned, decades, perhaps centuries ago. Reconditioning this large volume of soil by replacing lost nutrients, especially alkaline-rich minerals, takes a significant effort that requires fertilization over several years.

These results further demonstrate the efficacy of the fire mimicry approach. Not only is there a positive response when we apply these methods, there is also a negative response when we forgo these methods.

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Diseased oaks in Marin respond quickly to fire mimicry

Last April (2015) I was contacted by a home owner in Ross, CA (Marin County) regarding a very sick coast live oak tree (above) growing near his home. I promptly inspected the oak and found it was badly infected with a stem canker disease (probably Sudden Oak Death) and told him that I was not optimistic it could be helped. During my inspection I found few other oaks with SOD-like cankers. He asked that I try the fire mimicry techniques to see if they would help his sick oaks.

I visited the oaks last week to inspect and photograph their response. The photos show that the very sick oak has surprisingly responded with a nice flush of leaves in just one year. Several of the other sick oaks have also shown a good response (see below). The sick oak still has a severe stem canker infection and may not survive in the long run, but this is further evidence that we can improve the health and extend the lives of diseased oaks.

Oak restoration at Esalen Institute

This past Earth Day (April 22) I visited Esalen Institute in Big Sur and spoke on results of forest restoration using fire mimicry in California to the farm and garden staff. I also had the occasion to inspect and photograph several oaks that were treated with fire mimicry at an Earth Day event in 2012. These photos show pretty remarkable improvement in the canopy size and density of the oaks over the past four years, with one exception. The last oak in the photo sets below is in a very windy location. It has shown slight improvement over the years, but this year is exhibiting some browning of the leaves. I suspect this browning is a result of the very dry conditions in 2015. All of these oaks will receive another round of care this spring. Many thanks to the Esalen community for their support of this oak restoration effort!

Ponderosa pines responding to fire mimicry

There is a small grove of ponderosa pines up in Sonoma county being tended with fire mimicry techniques. I’ve been tracking their progress for 6 years and, while slow to respond initially, they are now showing noticeable improvement in canopy density. All the pines below have been treated EXCEPT for the last pine.

Marin and Sonoma oaks respond to fire mimicry

Below are photo comparisons of several coast live oaks that have been treated with fire mimicry techniques over the past few years. Some of the oaks have bleeding stem cankers, possibly Sudden Oak Death disease, though most appear uninfected. Positive responses in canopy density are visible in most of the oaks.

World Wood Day 2016 – Nepal

I recently participated on a project in Nepal in support of World Wood Day 2016, sponsored by the International Wood Culture Society. There were over 100 countries represented by the participants! Our project involved building a temple out of reworked rubble from the 2015 earthquake. Below are some images of the experience.