Climate Change Is Killing The World’s Oldest Trees

Photo: Bob Berwyn

by Bob Berwyn, via Summit County Citizens Voice

Colorado’s old lodgepoles aren’t the only forest giants that are dying. Around the world, the biggest, oldest trees that harbor and sustain countless birds and other wildlife, are meeting the same fate.

Three of the world’s leading ecologists say they’ve documented an alarming increase in the death rate of trees between 100 and 300 years old in many of the world’s forests, woodlands, savannahs, farming areas and even in cities.

“It’s a worldwide problem and appears to be happening in most types of forest,” said lead author Professor David Lindenmayer, of the ARC Centre of Excellence for Environmental Decisions and Australian National University.

“Large old trees are critical in many natural and human-dominated environments. Studies of ecosystems around the world suggest populations of these trees are declining rapidly,” he and colleagues Professor Bill Laurance of James Cook University, Australia, and Professor Jerry Franklin of the University of Washington, concluded in their report, published last week in Science.

“Research is urgently needed to identify the causes of rapid losses of large old trees and strategies for improved management. Without … policy changes, large old trees will diminish or disappear in many ecosystems, leading to losses of their associated biota and ecosystem functions,” the researcher said.

Lindenmayer said the first clue to the loss of big old trees came from examining Swedish forestry records going back to the 1860s. Then, a 30-year study of mountain ash (Eucalyptus regnans) forests in Australia confirmed not only that big old trees were dying en masse in forest fires, but also perishing at ten times the normal rate in non-fire years – apparently due to drought, high temperatures, logging and other causes.

Looking round the world, the scientists found similar trends at all latitudes, in California’s Yosemite National Park, on the African savannahs, in the rainforests of Brazil, the temperate forests of Europe and the boreal forests of the far north. Losses of large trees were also pronounced in agricultural landscapes and even cities, where people make efforts to preserve them.

“It is a very, very disturbing trend. We are talking about the loss of the biggest living organisms on the planet, of the largest flowering plants on the planet, of organisms that play a key role in regulating and enriching our world,” said Professor Bill Laurance of James Cook University.

“Large old trees play critical ecological roles. They provide nesting or sheltering cavities for up to 30 percent of all birds and animals in some ecosystems,” Laurance said. “They store huge amounts of carbon. They recycle soil nutrients, create rich patches for other life to thrive in, and influence the flow of water within landscapes and the local climate.

“Big trees supply abundant food for numerous animals in the form of fruits, flowers, foliage and nectar. Their hollows offer nests and shelter for birds and animals like Australia’s endangered Leadbeater’s possum (Gymnobelideus leadbeateri) – and their loss could mean extinction for such creatures,” he continued.

“In agricultural landscapes, large old trees can be focal points for vegetation restoration; they help connect the landscape by acting as stepping stones for many animals that disperse seeds and pollen,” he concluded.

The alarming decline in old trees in so many types of forest appears to be driven by a combination of forces, including land clearing, agricultural practices, man-made changes in fire regimes, logging and timber gathering, insect attack and rapid climatic changes, said Franklin.

“For example, populations of large old pines in the dry forests of western North America declined dramatically over the last century because of selective logging, uncharacteristically severe wildfires, and other causes,” Laurance added.

The researchers likened the global loss of big trees to the tragedy that has already befallen the world’s largest mammals, such as elephants, rhinos, tigers and whales, cautioning that almost nowhere do conservation programs have the time-frames lasting centuries, which are needed to assure the survival of old trees.

“Just as large-bodied animals such as elephants, tigers and cetaceans have declined drastically in many parts of the world, a growing body of evidence suggests that large old trees could be equally imperiled,” they warned.

The study triggered a call for an urgent world-wide investigation to assess the extent of big tree loss, and to identify areas where big trees have a better chance of survival.

Bob Berwyn is the editor of Summit County Citizens Voice. This piece was originally published at Summit County Voice and was reprinted with permission.

10 Responses to Climate Change Is Killing The World’s Oldest Trees

  1. ines says:

    Let me take a wild guess – fracking and drilling is polluting our earth. Don’t have to be a rocket scientist to figure that one out

  2. Gail Zawacki says:

    Not to detract from the vitally important implications of old tree decline, but in their narrow focus the authors of this study didn’t include the rather crucial and even more deeply frightening fact that young trees are dying off just as rapidly. Underpinning the overall decline is the inexorably increasing, persistent background level of tropospheric ozone.

    Hundreds of studies have been carried out over decades, by academics collaborating with forestry agencies and agronomists to establish without any doubt that ozone, although invisible, is highly toxic to vegetation, which absorbs it in the process of photosynthesis. Repairing damage to leaves and needles robs energy that should be devoted to developing roots systems, rendering plants more vulnerable to drought and wind.

    We saw this in both Irene and Sandy, where winds were not extraordinary and yet millions of trees fell over, knocking power out, their rotted interiors exposed.

    The most pernicious effect of ozone is to exhaust stored resources in trees making them more susceptible to pathogens, such as insects, disease and fungus. Most orthodox scientists blame these proximate attacks for tree decline, which is like blaming lung cancer on genetics instead of smoking.

    It will only be up for a week, but the reporter in this BBC radio programme about the astonishingly rapid spread of ash dieback makes it very, very clear when he visits Poland seeking the origins of the killer fungus, that not only are the old trees dying, but the young trees are going even faster

    Any serious and complete discussion of the horrific and rapidly accelerating extinction event that is affecting all species around the world which doesn’t factor in the underlying poisonous effect of air pollution is, forgive the pun, missing the forest for the trees.

    Please click on my name to visit my website for more information – I won’t add a link or likely this comment will be held forever in moderation purgatory. But there’s a page at the top of the blog where you can download a free book on this topic – also, I highly recommend “An Appalachian Tragedy” which can be obtained used on Amazon for very little and is an excellent primer on this subject.

  3. Greatgrandma Kat says:

    The old trees seem to be saying to us, we can no longer survive on man’s Eaarth.
    We were out walking with friends this last summer and I pointed out to them the rust-red color on the evergreens around our area. That it was on most of the trees we saw that day seemed to be a surprise to them. A few days after they left I got an e-mail from them, a really sad one telling me that on their trip home the red-rust was on trees just about everywhere they looked. They told me that they were passing the message on to everybody they could, to really look at the trees, to see what was happening. They also told me that on the trip to our place they truly hadn’t SEEN it at all.

  4. Ozone says:

    Its the ground level ozone. Background levels of ozone are now above 40 PPB, a level harmful to vegetation. Ozone makes plants more vulnerable to disease and insects.

  5. prokaryotes says:

    What have we become to not act on these kind of warning signs?

  6. Merrelyn Emery says:

    This is one of the most serious signs of climate change so far, far more serious than extreme weather or storms. Although many people these days don’t even look at them (as per Greatgrandma), terrestrial ecosystems, and us, won’t survive without them, ME

  7. paul magnus says:

    So whats happening… When systems tip, everything goes all at once!

    Were in for a wild ride….

    Chasing Ice movie reveals largest iceberg break-up ever filmed – video

  8. Mike Roddy says:

    Ozone is a huge problem, making trees less resilient, but industrial logging can finish off an ecosystem. I’ve seen former forests in Southern Oregon revert to scrubland after clearcutting and replanting attempts, and formerly wooded south facing slopes becoming bare.

    Tree mortality in the US has tripled since 1970. The Forest Service is not informing the public about this, and they remain joined at the hip with the logging industry.

    We need to slash our consumption of wood products just as much as we need to get off fossil fuels.

  9. Gail Zawacki says:

    Mike, have you seen the reports that China is at the center of illegal logging?

    Deforestation is a huge problem, one that started at least 2,000 years ago and gets worse every year.

    However, the paucity of comments on this thread is appalling and testament to how misguided the study is. Instead of raising an alarm, the loss of “big” trees allows them to be put in the category of “cute big polar bears and elephants”. In other words, who cares?

    Foresters should start explaining to the public in no uncertain terms that ALL trees – every age bracket, every species, every location – are dying off, and fast, because they are choking and drowning in pollution. This not only threatens replaceable products such as wood, nuts, fruit and shade – it threatens rainfall and one of the major CO2 sinks on the globe. Which kinda also threatens all of humanity.

    Instead of moaning sentimentally about aged trees, scientists need to start scaring the wits out of people about the loss of food and oxygen.