Upper slopes have additional water input from clouds.
Mean monthly temperatures range from 17-27o and vary inversely with elevation. Portions of the LEF were protected by the Spanish Crown as early as 1860 and transferred to the U.S. government in 1898. Since then the area of the protected forest has increased to 11,231 ha. The rich research tradition at the site is documented by the more than 500 publications based on work at the site. The most detailed study of the tabonuco zone was the Rain Forest Project of the U. S. Atomic Energy Commission, which took place from 1963 to 1968.