This article examines the role of forest surveys in postwar South Korea as a site of transnational knowledge production. Focusing on technical assistance programs led by the Food and Agriculture Organization (FAO) and financed by the United Nations Development Program (UNDP) from 1964 to 1973, it argues that forestry surveys based on aerial photography and statistical sampling functioned as key instruments for making forest landscapes legible, governable, and facilitating their economic exploitation. The study shows how FAO experts promoted standardized survey techniques rooted in European and North American forestry traditions, while Korean foresters selectively implemented and partially adapted these approaches. At the same time, surveys on erosion control and watershed management demonstrated the entanglement of colonial legacies with Cold War development politics. The article highlights three main findings: First, forest surveys facilitated the circulation of a global forestry practices centered on industrial production and resource management. Second, Korean actors exercised agency in shaping project priorities, often favoring data acquisition and technical training over externally proposed management models. Third, the application of aerial photography enabled large-scale state interventions, including reforestation plans and the eradication of shifting cultivation. By situating South Korea within broader Cold War development networks, the article contributes to histories of global technoscience in eco-governance.