Now, a more detailed satellite observation system is able to detect selective logging, and the findings show much more widespread timber harvests than had been thought, according to a report in Friday's issue of the journal Science.

Annually, selective logging disturbs an area totaling about the size of Connecticut, according to lead author Gregory Asner of the Carnegie Institution of Washington and Stanford University.

"Selective logging negatively impacts many plants and animals and increases erosion and fires. Additionally, up to 25 percent more carbon dioxide is released to the atmosphere each year, above that from deforestation, from the decomposition of what the loggers leave behind," Asner said in a statement.

Illegal logging was even discovered in some protected national reserves, parks and indigenous lands, the researchers found.

"We expected to see large areas of logging, but the extent to which logging penetrates deep into the frontier is much more dramatic than we anticipated," said co-author Michael Keller of the U.S. Forest Service.