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 ForestForests' Retreat: Page 10 Throughout the world, biologically diverse natural forests are being replaced with tree farms of fast-growing pine or eucalyptus. In Japan, cedar is planted over millions of acres for harvesting. The goal of these farms is to replace old-growth forests that take hundreds of years to mature with trees that can be harvested in 30 to 50 years. Large amounts of herbicides and pesticides are applied to prevent the growth of "undesirable" plants and to control insects. These tree farms have contaminated water tables, destroyed natural diversity, and eliminated countless life forms crucial to maintaining the ecological balance of the planet. Moreover, many are now failing even in their goal of producing fast-growing, healthy trees because of a lack of understanding of ecological systems and natural forest functioning. Tree farms are frequently swept by disease and, in the case of Japan's cedar plantations, which cover 10 million acres, shallow roots have resulted in trees blown over in windstorms and landslides after heavy rains. A healthy forest has many species of trees. This diversity discourages insect pests, which tend to specialize in individual species, from spreading and sweeping through the forest, killing all the trees. The variety of trees in a natural forest also means that many are deep-rooted or have root mats that anchor the soil from erosion.
An added environmental threat posed by tree farms is the use of genetically engineered seedlings, whose effects on ecosystems are not yet known. By transplanting genes from other species of trees--and even animals-- into these unnatural trees, the possibility that their seeds could spread to the wild and contaminate natural trees and plants is very real.
Major disruptions in pollination occur in fragmented forests. Natural tropical forests, with hundreds or even thousands of species of trees, have evolved complex systems of reproduction. Because other trees of the same species might be miles away, trees send their pollen far and wide. Insect pollinators travel great distances to find trees of the same species. Biologists have found that even in selectively logged forests, trees were not being pollinated naturally because others of their kind were removed or became too distant; some species self-pollinated, causing in-breeding, while others simply died out (Yoon 1995b). These biologists concluded, "Even the forests that appear the healthiest but are being selectively logged or otherwise thinned may be endangered in the long run by an increase in less desirable inbred seed" (Yoon 1995). Inbred stock usually loses vigor and ability to reproduce over the long run. This is an ominous finding considering that many conservation organizations and international logging companies have endorsed certain "sustainable" logging programs, urging the public to purchase products identified as such. Moreover, many of these ancient trees tower 200 or more feet, with wide buttresses at ground level to anchor them in the thin tropical soil. Such trees may have stood on the forest floor for 1,000 years and are living monuments, treasures to be preserved, not raw material for packing cartons, furniture or paper pulp.
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