In the matter of the spotted owl and the old-growth forests of the Northwest, President Bush and others say they want to maintain some ''balance'' between the interests of the economy and the interests of the environment. But what kind of balance can there be when loggers have already cut down 90 percent of the old-growth forests? According to The Post, of the 25 million acres of old-growth forest that once existed, only 2.3 million acres remain. If there was really any interest in balancing interests, logging would have been halted a long time ago.

At current rates, it appears that the old-growth forests still available for logging will be gone in 10 or 15 years. At that point it is certain that loggers will lose their jobs. I find it hard to believe that we could be so short-sighted as to eliminate for all time what is left of these magnificent forests just to preserve for a few more years a few thousand jobs that are doomed anyway.

ERIC N. LINDQUIST Washington

As a former resident of Washington state who returns annually to the Pacific Northwest, I can attest to the growing frustration of those who see the devastation of some of this country's most magnificent stands of Douglas fir, spruce, hemlock and cedar.

The administration implies that the U.S. Forest Service has overreacted to the spotted owl issue, playing on the popular misconception of the Forest Service as protector of federal forestlands. The Forest Service was established to safeguard the nation's forests from the lumber barons of the early 20th century, but subsequently developed a cozy relationship with the timber industry and actively promotes timber harvest over other forest uses. The result in the Pacific Northwest has been widespread clearcuts, many on slopes so steep that soil erosion inhibits reforestation and a spaghetti-like network of logging roads constructed at public expense that snake ever deeper into the Cascade and Olympic mountains.

That the Forest Service proposal, responsibly recommending to preserve owl habitat, is opposed by the administration speaks volumes about the administration's real position on the environment.

Better ways exist to address the economic impact of a reduced timber base than cutting all the old growth, which would merely delay job losses. Much Northwest timber is exported, primarily to Japan, as raw logs. Processing of timber by Pacific Northwest mills would greatly increase the economic base. States should be allowed to restrict exports of logs from state lands, and exported logs should be heavily taxed, allowing domestic mills to more successfully bid for logs that otherwise would be exported, and creating funds for research to promote long-term sustained forestry. Funds to support economic diversification for communities most affected should be increased.

We cannot accuse other countries of permitting the destruction of the world's tropical rain forests when we are doing the same to our own temperate rainforests. LEE SIEBERT Arlington