It is widely accepted that a major historic pathway to agriculture in the tropics has been via the management of forest and reliance on tree resources. Using ethnographic and ethnobotanical data from Seram in the Moluccas, this article illustrates how this might have happened in one part of Island Southeast Asia. Several species of the genus Canarium produce proteinaceous nuts that have been ethnographically, historically, and prehistorically shown to be an important part of local diets. To understand how food-procurement systems evolve, we need to examine the biocultural dynamic established over the long term between different species, types of arboriculture, and cultivation strategies. One factor was likely subsistence pressure, but exchange has also been an important driver in relation to procurement of Canarium in particular and to the modification of forest landscapes more generally, hence the term "landscapes of exchange." While theorists tend to assume dietary need is the main cause of agricultural change, the social and ritual significance of particular species often drives ecological and genetic change in anthropic contexts.