Effect of Shade Trees on Yields of Five Crops in the Humid Mountain Region of Puerto Rico

Abstract

The effects of trees, providing about 50 percent of shade, on yields of tobacco, corn, taniers, plantains, and bananas were determined in the Mountain Region of Puerto Rico, with annual rainfall of about 73 inches and a mean annual temperature of 72° F.  Shade trees severely reduced yields of taniers and corn, reduced those of plantains only slightly, and did not affect yields of tobacco. Bananas produced twice as high yields of marketable fruit under shade than in full sunlight because of reduced damage by leaf spot (Sigatoka) disease. The possibility of converting abandoned, shaded coffee plantations to high productivity, together with conservation, by growing bananas in undisturbed soil with natural ground cover under shade trees is promissing.