Abstract
Unmanned aerial system(UAS) has the merits of easy-operating, high mobility, economics and safety . The technology of aerial photo can provide instant high image resolution photo data of forest stand, and the distribution of forest resource. On the aspect of terrain change, the UAS can also provide sub-meter level digital surface model(DSM). This study try to apply above technique to collect instant data of forest land and stand. The mathematical model will be established by considering the costs of forest road construction and maintenance, logging and transportation under the restriction of terrain index. The optimizing forest road density will to calculated for bamboo tree and plain area. The results can be reference for machinery application and forest management.