Dutch foresters asserted that upland forest cover was essential to maintain balanced hydrological cycles. They sustained this argument despite contrary empirical evidence and resistance from the colonial administration who were concerned more on local livelihoods. Underpinning this belief was a conviction that customary systems of land tenure and use were inappropriate and destructive. The Dutch foresters used scientific discourse to justify the State's control of 120 million hectares of land as forest reserves, instigating a pattern of land control that has endured to this day. The ongoing application of past designations is the driver of this paper to explore the arguments behind the decisions of Dutch Colonial Government and its implications to current policy framework. The objective of the paper is to show that science became an instrument of the Forest Service during the Dutch colonial era, as a means of exerting greater power and control over the forested land.