ForestryFriend

There is a reason why forestry seldom, if ever, causes species to become extinct

We tend to think that forests need our help to recover after destruction, whether by fire or logging. Of course this is not the case. Forests have been recovering by themselves, without any assistance, from fires, volcanoes, landslides, floods and ice ages, ever since forests began over 350 million years ago.

Consider the fact that 10,000 years ago all of Canada and Russia were covered by a huge sheet of ice under which nothing lived, certainly not trees. Today, Canada and Russia account for 30 percent of all the forests on earth, grown back from bare rock. Go to Alaska where the glaciers are retreating due to the present warming trend, and you will see that from the moment the rocks are laid bare to the sun, it is only 80 years until a thriving new ecosystem is growing there, including young trees

It follows from this that every species which lives in the forest must be capable of re-colonizing areas of land that are recovering from destruction. Indeed, forest renewal is the sum total of all the individual species returning to the site, each in their turn, as the forest grows back. In ecology, this is known as dispersal, the ability to move from where you are and to inhabit new territory as it becomes available.

In humans, we call this migration, but it is the same thing. Dispersal is an absolute requirement for natural selection and the survival of species. No species could exist if it were not capable of dispersal. Therefore, so long as the land is left alone after the forest is destroyed, the forest will recover and all the species that were in it will return.

Fire has always been the main cause of forest destruction, or disturbance, as ecologists like to call it in order to use a more neutral term. But fire is natural, we are told, and does not destroy the forest ecosystem like logging, which is unnatural. Nature never comes with logging trucks and takes the trees away. All kinds of rhetoric is used to give the impression that logging is somehow fundamentally different from other forms of forest disturbance.

There is no truth to this. It is true that logging is different from fire, but fire is also very different from a volcano, which in turn is very different from an ice age. In fact, no two fires are ever the same. These are differences of degree, not kind.

Forests are just as capable of recovering from destruction by logging as they are from any other form of disturbance. All that is necessary for renewal is that the disturbance is ended, that the fire is out, that the volcano stops erupting, that the ice retreats, or that the loggers go back down the road and allow the forest to begin growing back, which it will begin to do almost immediately.

If you don’t think fire destroys the ecosystem, you should try counting the species left alive after a severe forest fire. A hot wildfire in a dry pine forest not only kills every living thing above the ground, it also burns the soil, killing the roots and seeds, basically sterilizing the site and leaving it lifeless. Yet it is often only a few years after such a fire that the land is alive with grasses and flowers again.

Everywhere in the world there are pioneer plants which produce seeds with fluff on them. They can carry for 100 miles on a light breeze, looking for a place to settle in the open sun and germinate. A recently burned forest is a perfect place for these seeds; the shade of the trees is gone allowing full sun to reach the ground, and the ash from the fire provides nutrients for new growth.

In Yellowstone National Park, fire burned over one million acres in 1988. Even after eight years, the most severely burned areas off the park have very little vegetation growing back. This is partly due to the very short summers at 8000 foot elevations, but also because extremely hot fires not only remove nitrogen from the soil but also vaporize the phosphorous, thus depleting the soil of two of the three most essential nutrients. While nitrogen is returned to the soil relatively quickly through the action of nitrogen fixing bacteria, phosphorous must be weathered from the minerals in the soil. This may take 50 or 100 years but eventually the soil will heal and a new forest will emerge.

In some areas of the Yellowstone fire the soil was wet at seepage sites, and even though everything above the ground was killed, the seeds of the pine and other species survived in the soil. Here a new forest is growing back quickly and the new pines will produce seeds in 10 or 15 years. These seeds will gradually march across the landscape, reforesting the land where the seeds were burned.

In order to witness total destruction by nature, there is no better place to go than Mount St. Helens in Washington State. When this volcano blew up in 1980 it destroyed over 150,000 acres of forest, much of it old growth growing on the flanks of the mountain. Interestingly, the forest that was destroyed was in two distinct jurisdictions. Part of it was federal public lands, the Gifford Pinchot National Forest, controlled from Washington DC. Part of it was private timberlands owned by the Weyerhaeuser Corp. based in Tacoma, Washington.

The US government re-designated the portion of their land that was destroyed the Mount St. Helen’s National Volcanic Monument, "where nature will be permitted to recover, unaided by human beings, for the discovery of science." 18 years after the initial blast the Volcanic Monument still looks like a desert. The dead trees are still lying where they were blown over or had their tops blown off by the initial blast. A thick layer of volcanic ash then settled out, making a very sterile seed bed for seeds blowing in on the wind. Only a few hardy nitrogen-fixing plants, such as slide alder, have been able to take root in the poor soil

Weyerhaeuser took a completely different approach. First they salvage logged 85,000 three-bedroom homes worth of timber from their land in two years following the eruption. By bringing in heavy equipment and dragging the big logs around, they broke through the volcanic ash everywhere, exposing the fertile soil beneath it. This created a much more fertile seed bed for seeds blowing in on the wind, a classic case of site disturbance, or site preparation as it's called when we do it on purpose, increasing the fertility of the site. Something every farmer who plows their fields knows.

Then they planted two-year-old Douglas fir seedlings that were advanced enough to get their roots down through the ash into the healthy soil beneath. Today these seedlings are over 20 feet tall and will produce a commercial crop of timber in the year 2026.

The contrast between the National Volcanic Monument and Weyerhaeuser's land offers proof that a couple of interventions by people can make a dramatic difference to the way in which an ecosystem recovers after a natural disaster such as a volcano.

	Forestry---The Forest’s Friend or Foe?
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	There is a reason why forestry seldom, if ever, causes species to become extinct We tend to think that forests need our help to recover after destruction, whether by fire or logging. Of course this is not the case. Forests have been recovering by themselves, without any assistance, from fires, volcanoes, landslides, floods and ice ages, ever since forests began over 350 million years ago. Consider the fact that 10,000 years ago all of Canada and Russia were covered by a huge sheet of ice under which nothing lived, certainly not trees. Today, Canada and Russia account for 30 percent of all the forests on earth, grown back from bare rock. Go to Alaska where the glaciers are retreating due to the present warming trend, and you will see that from the moment the rocks are laid bare to the sun, it is only 80 years until a thriving new ecosystem is growing there, including young trees It follows from this that every species which lives in the forest must be capable of re-colonizing areas of land that are recovering from destruction. Indeed, forest renewal is the sum total of all the individual species returning to the site, each in their turn, as the forest grows back. In ecology, this is known as dispersal, the ability to move from where you are and to inhabit new territory as it becomes available. In humans, we call this migration, but it is the same thing. Dispersal is an absolute requirement for natural selection and the survival of species. No species could exist if it were not capable of dispersal. Therefore, so long as the land is left alone after the forest is destroyed, the forest will recover and all the species that were in it will return. Fire has always been the main cause of forest destruction, or disturbance, as ecologists like to call it in order to use a more neutral term. But fire is natural, we are told, and does not destroy the forest ecosystem like logging, which is unnatural. Nature never comes with logging trucks and takes the trees away. All kinds of rhetoric is used to give the impression that logging is somehow fundamentally different from other forms of forest disturbance. There is no truth to this. It is true that logging is different from fire, but fire is also very different from a volcano, which in turn is very different from an ice age. In fact, no two fires are ever the same. These are differences of degree, not kind. Forests are just as capable of recovering from destruction by logging as they are from any other form of disturbance. All that is necessary for renewal is that the disturbance is ended, that the fire is out, that the volcano stops erupting, that the ice retreats, or that the loggers go back down the road and allow the forest to begin growing back, which it will begin to do almost immediately. If you don’t think fire destroys the ecosystem, you should try counting the species left alive after a severe forest fire. A hot wildfire in a dry pine forest not only kills every living thing above the ground, it also burns the soil, killing the roots and seeds, basically sterilizing the site and leaving it lifeless. Yet it is often only a few years after such a fire that the land is alive with grasses and flowers again. Everywhere in the world there are pioneer plants which produce seeds with fluff on them. They can carry for 100 miles on a light breeze, looking for a place to settle in the open sun and germinate. A recently burned forest is a perfect place for these seeds; the shade of the trees is gone allowing full sun to reach the ground, and the ash from the fire provides nutrients for new growth. In Yellowstone National Park, fire burned over one million acres in 1988. Even after eight years, the most severely burned areas off the park have very little vegetation growing back. This is partly due to the very short summers at 8000 foot elevations, but also because extremely hot fires not only remove nitrogen from the soil but also vaporize the phosphorous, thus depleting the soil of two of the three most essential nutrients. While nitrogen is returned to the soil relatively quickly through the action of nitrogen fixing bacteria, phosphorous must be weathered from the minerals in the soil. This may take 50 or 100 years but eventually the soil will heal and a new forest will emerge. In some areas of the Yellowstone fire the soil was wet at seepage sites, and even though everything above the ground was killed, the seeds of the pine and other species survived in the soil. Here a new forest is growing back quickly and the new pines will produce seeds in 10 or 15 years. These seeds will gradually march across the landscape, reforesting the land where the seeds were burned. In order to witness total destruction by nature, there is no better place to go than Mount St. Helens in Washington State. When this volcano blew up in 1980 it destroyed over 150,000 acres of forest, much of it old growth growing on the flanks of the mountain. Interestingly, the forest that was destroyed was in two distinct jurisdictions. Part of it was federal public lands, the Gifford Pinchot National Forest, controlled from Washington DC. Part of it was private timberlands owned by the Weyerhaeuser Corp. based in Tacoma, Washington. The US government re-designated the portion of their land that was destroyed the Mount St. Helen’s National Volcanic Monument, "where nature will be permitted to recover, unaided by human beings, for the discovery of science." 18 years after the initial blast the Volcanic Monument still looks like a desert. The dead trees are still lying where they were blown over or had their tops blown off by the initial blast. A thick layer of volcanic ash then settled out, making a very sterile seed bed for seeds blowing in on the wind. Only a few hardy nitrogen-fixing plants, such as slide alder, have been able to take root in the poor soil Weyerhaeuser took a completely different approach. First they salvage logged 85,000 three-bedroom homes worth of timber from their land in two years following the eruption. By bringing in heavy equipment and dragging the big logs around, they broke through the volcanic ash everywhere, exposing the fertile soil beneath it. This created a much more fertile seed bed for seeds blowing in on the wind, a classic case of site disturbance, or site preparation as it's called when we do it on purpose, increasing the fertility of the site. Something every farmer who plows their fields knows. Then they planted two-year-old Douglas fir seedlings that were advanced enough to get their roots down through the ash into the healthy soil beneath. Today these seedlings are over 20 feet tall and will produce a commercial crop of timber in the year 2026. The contrast between the National Volcanic Monument and Weyerhaeuser's land offers proof that a couple of interventions by people can make a dramatic difference to the way in which an ecosystem recovers after a natural disaster such as a volcano.
	This is an excerpt from “Trees Are the Answer” by Patrick Moore, co-founder of Greenpeace. Printed by Permission. To read the entire article, please go to this link: http://www.greenspirit.com/trees_answer.cfm
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