Abstract
P. macrocarpus is a medium to large (usually up to 25 m tall, but sometimes up to 35 m tall) tree native to Myanmar, northern Thailand, Cambodia, Laos and Vietnam. It is a light-demanding, frost sensitive species, and natural regeneration is generally best in dry, open forest, and in disturbed areas. In its native range it grows best on sandy loams (Hundley, 1957). In Puerto Rico, it has grown well on soils ranging from sandy loams to well-drained clays (Francis, 1989). A volume table is available for a trial plantation in Laos; trees had attained an average height of 14.5 m after 13 years (Hjelm, 1995). Although small trees coppice well, coppicing ability declines with size.
Notes on Pinus kesiya and P. merkusii and their natural regeneration in watershed areas of northern Thailand.