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 ForestForests' Retreat: Page 8 Many of the last old-growth forests have been cut for throwaway products such as shipping crates, concrete forms, plywood, chopsticks and newsprint. Virgin rainforests in southeast Asia, Australia, Alaska, Russia and British Columbia are being logged to supply the enormous demand for such products, destroying entire ecosystems in the process. The United States and Japan have played major roles in the logging and trading of lumber at extremely low prices for industrial uses (Yates 1992). When one country's forests are stripped, loggers move on to another. In this way, the great Philippine forests of Pliocene trees and Central American forests were cut in the mid-20th century, followed by the teak forests of Thailand and the hardwoods of Indonesia and West Africa. These areas have lost 80 percent or more of their forest cover, and loggers have now moved on to Central Africa, Burma, Belize and Amazonian South America. Brazil's beautiful rosewood trees have already been logged to near extinction. The World Conservation Monitoring Centre of Cambridge, UK, conducted a study on commercial logging and found that 304 tree species from Asia and Africa were threatened with extinction by trade (Bohan et al. 1996). Fifteen species of commercially logged trees are listed by the Convention on International Trade in Endangered Species (CITES) in the most endangered category.
In response to criticism about clearcutting, some logging companies and conservation organizations endorse selective cutting, or cutting only certain species of trees or trees of a certain age. Yet such logging is also destructive. One United Nations (UN) Food and Agriculture Organization (FAO) study found that selective cutting destroyed as much as 70 percent of forest cover when conducted totally irresponsibly and, on average, destroyed 30 to 40 percent of the trees (Bohan et al. 1996). Destruction of non-target trees occurs with the construction of logging roads and use of heavy equipment to extract trees; when tree canopies and vines entangle one another, many trees are brought down, although only one may be cut. A study in French Guiana found that an average of 57 trees are killed for every tree extracted by selective logging (Bohan et al. 1996). Research on logging in Sarawak, a Malaysian state on Borneo, found that of every 26 old-growth trees cut, 33 others were destroyed or damaged, and canopies were broken, isolating animals who will not cross open spaces (Yates 1992). The thin tropical soil was also compacted and exposed, preventing natural regeneration of the forest (Yates 1992).
Many logging companies claim that by cutting mature trees selectively on 30- to 70-year rotations, they are conserving forests (Collins 1990). By definition, no tree older than 70 years can exist in such a forest. Such logging will end in destruction of the ancient and diverse forests, with trees 1,000 or more years old harboring a wealth of species that can only grow and prosper in old-growth forests. The more diverse a forest, the more stable ecologically, and logging tends to impoverish diversity by selectively removing certain commercially valuable species.
Thousands--and perhaps millions--of species depend on primary, virgin forests and cannot adjust to second-growth or logged forests. How many, and which species they are, however, is only partially known. Even scientists specializing in forest wildlife have not determined all the species that fall into this category, especially in complex tropical forest ecosystems. Unfortunately, this knowledge is often acquired too late, after logging has taken place and endemic species have disappeared. Logging operations are proceeding with such speed, and the scientists chronicling the damage are so few in number, that in terms of threats to plants and wildlife, only the tip of the iceberg is being documented.
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