Chapter 65. International Forestry Cooperation 16 U.S. Code §4501. Forestry and related natural resource assistance 16 U.S. Code §4502. Tropical deforestation assessment and assistance 16 U.S. Code §4502a. Tropical forestry research and assistance 16 U.S. Code §4503. Institute of Tropical Forestry in Puerto Rico 16 U.S. Code §4503a. Institute of Pacific Islands Forestry 16 U.S. Code §4503b. Hawaii Experimental Tropical Forest 16 U.S. Code §4503d. Definitions 16 U.S. Code §4504. Administrative provisions 16 U.S. Code §4505. Authorization of appropriations