Cost and Labor Assessment of UAV-Based, Vehicle-Based, and Ground-Based Survey Methods for Planning Vine Control Operations in Forest Landscapes: An Activity-Based Costing Case Study from Hwasun-gun, Republic of Korea

Vine control is a recurring silvicultural treatment, and the survey preceding it determines where treatment is directed. However, no comparative cost basis exists for choosing among survey methods, and the labor norms currently applied in the Republic of Korea were developed for drone-based pest surveillance rather than vegetation mapping. This study is an activity-based costing case study, conducted in Hwasun-gun, Republic of Korea, that places unmanned aerial vehicle (UAV)-, vehicle-, and ground-based methods for vine distribution mapping on one transparent cost model. Six distribution types were surveyed in September–October 2022 using a fixed-wing UAV (WingtraOne GEN II), a rotary-wing UAV (DJI Mavic 2 Pro), and vehicle-based route observation, yielding 1281 occurrence records. All methods were costed on an identical fully loaded basis and classified by the output tier delivered. For a 300 ha areal unit, the fixed-wing UAV was the least expensive method delivering delineation-grade output (KRW 10,278 ha−1), ahead of the rotary-wing UAV (KRW 12,299 ha−1) and a walking benchmark (KRW 59,016 ha−1). For a 2 km roadside corridor, reconnaissance-grade vehicle survey cost KRW 287,511 km−1, approximately 40%–45% of the cost of either UAV platform, although orthophoto interpretation added 15.2% to the vine area the vehicle-based survey had mapped. Cost-efficiency followed the spatial form of the target distribution and the output tier required rather than the platform. The absolute figures are specific to Korean cost-estimation rules, one county, one late-season window and one species (kudzu); the trade-offs they express are what transfer elsewhere. Vehicle-based surveys therefore suit linear distribution types and road-accessible forest edges; UAV survey areal types requiring delineated boundaries; and ground inspection verification and point-type features.