Remotely sensed, high spatial resolution images have great potential in assisting vegetation management in power line corridor. With the wide use of object-based approaches in remote sensing image analysis, individual tree crown delineation becomes a key research focus to improve the accuracy of plant information extraction. Although many algorithms have been investigated for individual tree crown delineation, no one algorithm seems suitable for all situations. As such, this paper investigates the applicability of several tree crown delineation techniques for complex environments in power line corridors. The advantages and limitations of these algorithms and prospective improvements are discussed. Initial experiment results on tree crown delineation employing JSEG are presented and compared with Mats Erikson’s region-growing method.