Chiu-Nan Lai, Ph.D.
You don’t have to destroy the forest to harvest trees
For many years, scientists have warned that ecological bankruptcy may cause global warming and rising sea levels, which in turn will bring disasters. These have now become a reality. The forest re in California this year is most serious of all. The range of fire is unbelievable; this has definitely fueled the climate disasters. The typhoons in China’s coastal areas are unprecedentedly strong, and some of the islands in the oceans are now below sea level. Seawalls must be built to protect these coastal cities. The reason that the ecological climate would deteriorate to this extent is because human being in recorded history has made distinction between “your” home versus “my” home. Specifically, conquerors treated “strangers” afar very differently from the way they treat “their own people”.
“Your” forest can be cut down, “your” mines can be fully exploited, and the wild animals, birds and fishes in “your” home can all be hunted and killed. However, there is only ONE earth and all of us share the same ONE home. We live on the same land; we share the same oceans, the same air and the same climate. Air pollution does not just stay in the sky of “your” home, and rainwater is also connected.
Even thousands of years ago, it could be seen that countries and conquerors that did not cherish natural resources had unhappy endings.
Two thousand years ago, the Roman Empire led expeditionary army to cut down trees in Lebanon, North Africa and the Mediterranean. They utilized the same logging method used today to cut down all the forests; and the consequences of deforestation is the same as those faced today as well. Most of the land became desert and the Roman Empire also disappeared. In the seventh century, in order to build military ships, Greeks cut down all their trees and hence lost their forests. Only in recent times, Libya started to re-grow their forest. Their climate and agriculture improved as a result. The Sahara Desert in North Africa is the largest desert on Earth. It is bigger than the Asian Gobi Desert (Gobi is Manchurian word for desert). In the Gobi Desert, there were traces of rivers and evidence of the ancient ginkgo trees, indicating previous existence of forests and good eco-system.
Apart for logging purpose, the recent land desertification is also due to agricultural and policy reasons. During the Japanese era, cypress trees in Taiwan were cut down and sent to Japan. In the seventies and eighties, Brazil offered free forestland to attract 500,000 people to the forest to cut down trees and converted the forest to farmland. A total of 1,100 miles of road was built. The forest topsoil was very thin and could not withstand the damage from fertilizer and the demand for crops. Within just a few years, the land could no longer be used for farming. As a result, trees in deeper part of the forest had to be cut down. The repeated process of destruction caused the disappearance of forests. This is also happening in India, Indonesia and Malaysia. In 1988, the satellite infrared camera operated by NASA showed that there were six thousand different res in the Amazon rainforest every day. The financial value of mono crop and its ability to absorb carbon dioxide cannot replace the original rainforest or any virgin forest. The abundance of the original forest species is also irreplaceable. The resources of Rainforests are mostly above the forest ground, not much is stored in the soil itself.
Desertification caused by deforestation can be repaired. California was originally a redwood forest. 150 years after the white people arrived in California, most of the forests were cut down and the climate became dry and the land impoverished.
Bob Cannard, who lives in North California, has continually restored the watershed and has greatly raised the groundwater level on the land where he farmed for 40 years. During the four or five years of drought in California, the streams owing through his farmland did not dry out.
When Bob first arrived at the land, the streams would dry out a week after the rain. The riverbed was six feet deep and ten feet wide. He restored the watershed by bundling branches and stones with wire to block the river and slow down the flow of water. He also blocked the silt from being washed off. The water that flowed out of the farm was clear. Throughout the years, the speed of water flow slowed down, and there was more water flowing in than out of the farm. The riverbed gradually became wider and shallower, and became one hundred feet wide and three inches deep. A variety of trees such as oak, poplar, etc., grew along the shores of the river. There are many wild plants such as ferns amaranth and so on. In his book New Century Farming, Bob mentioned that his view is contrary to the practice of the average person: “Others suggest digging holes to divert water, but I suggest filling up the holes.” The consequences are different. Because of the improvement of the groundwater level, his peach and lemon trees do not need watering. On the contrary, the groundwater level of farms that have diverted water has declining groundwater level annually. Especially in the dry years of California, many wells went dry and deeper wells had to be dug. This is the process of desertification.
Farms that consulted with Bob have made improvements using his methods. Generally, it is possible to see the result within ten years: an increase in the function of the land to retain water and raised groundwater level. Green String Farm, the farm he founded, has raised the riverbed by six inches and restored the original half-acre of swamp.
The common way of controlling desert only considers planting trees and then utilizes huge engineering projects to introduce water. If the natural process were followed, not much resources would be required. Moreover, by working on the fundamentals via increasing the groundwater level and protecting the watershed will increase the success rate. Bob’s principle in preserving soil is to go to the watershed at the edge of desert, use wire to tie the stones to block the area where water washes away the soil. Silt will be prevented from being washed away. Then, in this area, plant wild plants that grow well in the desert. The roots of these plants can stabilize the soil and improve the soil. The hills of the water source will become green first, and then the plains will also be green. Maybe in ten or twenty years, some strong crops such as daikon radish can be planted, and limited grazing may be allowed. Perhaps fifty years later it can become fertile land.
Restoring desert is a 100-year project. It takes more than just a few years to see results. Land desertification is caused by many years of destruction; thus it will also need many years to repair the land. Just like the Native Americans’ philosophy that says, “we must consider the welfare of the next seven generations” If the ancestors from all places had thought of the next seven generations, we would not have to encounter such a big climate disaster now. If we do not wake up now, we will leave no proper living condition for our future generations to survive on the earth. And if we decide to come back to earth, there will also be no place for us!
Since clear cutting of the forest causes desertification, what can be done to preserve the existing forests and yet meet the demand for wood to satisfy modern life? In fact, trees can be cut in a sustainable way, not only that the forest can be preserved but a continual supply of wood can also be realized. Wildwood, a tree farm located in Vancouver Island on the southwestern part of Canada, harvests timber in a “tree selection system” since 1945. The forest is still in existence and has a continuous supply of trees for logging. The original forest owner, Merv Wilkinson, cut the same amount of wood as the annual growth rate of the forest. For example, between 1985 and 1989, Wildwood grew 270, 000 board feet of timber, so the same quantity of trees was cut in the ninth harvest in January 1990.
As long as the tree trunk is over six inches in diameter, it is included in the supply, including firewood, fences, pillars and timber. Sustainable logging must be selective. Logging can be done continually or periodically as long you do not cut over the annual growth or else you drain the “savings” of trees. Merv left an extra five percent of trees as “interest” on the forest as future investment for the forest.
Wildwood is also a “farm”. Most farms harvest every year, but his tree farm harvests once every five years. To protect Wildwood or other forests, he suggested following several principles as listed below.
- Be clear about the annual growth of trees.
- Understand the varieties and values of trees in different areas.
- Prune appropriately so that trees have enough light to grow.
- Allow trees to propagate naturally.
- Protect the soil, leave the land with enough woody debris.
- Avoid soil erosion when building roads.
- Time and energy invested brings the owner good income.
Protecting forest soils is very important in forest management. Keep the woody debris, leaves, pine needles and wood dropped from trees so that they can break down naturally. The common practice nowadays is to burn the remaining branches and wood chips after cutting down the trees; this practice is very harmful to the soil. In North America only one eighth of an inch is added to the surface of the soil every century. Man- made fires have destroyed several hundred years of topsoil. The growth of trees depends on surface soil. Subsoil (Bottom layer) can only provide support. If the topsoil is burned or crushed by heavy machine, soil erosion occurs, and the new forest would not be able to regenerate.
How can forests have the next generation? Merv always depended on natural regeneration rather than growing and planting tree seedlings. Firstly, in the forest, he would select the “mother tree” which looks very good, has no genetic defects, and has fruits (for example pine) with good shape. It takes a few seasons to observe to see if the tree is suitable to be a mother tree. Different varieties of mother trees are retained in different regions. Trees grow faster in the shade of the mother tree. Merv has conducted experiments, comparing the growth of a row of tree seedlings planted on the bare land, with a row of tree seedlings planted under the shade of trees. The result showed that the growth rate of tree seedlings growing under the shade was 15 percent faster.
Generally, industrial plantations would transplant tree saplings to a land that has been chopped bare of trees. Trees take eight to ten years to clear the trauma of being transplanted. And then, with overly strong light due to the lack of shade, and barren soil, the saplings are once again traumatized. Trees grown this way often die after a few years.
Another method is to let the roots of trees that had been chopped o to continue to grow into small trees. On the tree stem, preferably on the north part of the stem, keep one or two branches that are closest to the roots. These branches will grow into new trees. If the age of the mother tree is not very old, it can grow many new trees, sometimes up to eight or ten trees. An old tree root can continue to nourish saplings for many years. Fir trees can be grown this way. But once a pine tree is cut, it is wounded and can no longer grow small trees.
Notes: Wildwood: A Forest for the Future by Ruth Loomis with Merv Wilkinson.
This book is no longer in publication, as both the author and the publisher are about eighty years old. Merv had accidentally learned about sustainable forest management. At that time, he was taking short-term courses in college with the thought of going into animal husbandry. In college, he met a professor from Denmark and learned how Scandinavians took care of the forest. The professor had previously taught forest management in Denmark and Sweden, but Canada did not have a forest management department in 1938, so the professor taught Merv personally, guiding him in learning the implementation of forest management methods, and in completing the course in theory and practical management. After Merv passed the exam, the professor said to him: “Your study has just begun, continue to learn.” For years Merv learned about tree cutting, logging management and forest management. Now because of his age, he has sold the forest to a forest environmental group so that the group can continue his work.
Nowadays, most of the tree loggings are done by large commercial enterprises. Usually, the supporters of these enterprises are their shareholders, and you may be one of them. Please check on the companies that you invest in. If you have an impact, please influence them on the way of logging. A sustainable method is the best way of investment. “We will always have wood to burn as long as forests are preserved”. Let us remember that!
The original Chinese article was published in the November 2016 issue of Lapis magazine and is accessible online http://www.lapislazuli.org/tw/index. php?p=20161101.html