37.3% of pine wilt-infected trees remain untreated; control rate at 62.7%

Data obtained from the Korea Forest Service by Democratic Party lawmaker Yoon Jun-byeong showed that 1,111,472 of the 1,772,985 trees infected with pine wilt disease this year had undergone control measures. The remaining 661,513 trees had not, while the control rate fell from 89.4% in 2025 to 62.7% this year.

Pine wilt disease kills pine trees when nematodes introduced by insect vectors such as the Japanese pine sawyer disrupt the movement of water and nutrients inside the trees. Infected trees are difficult to treat, making removal a primary response; failure to remove them before the insect vectors become fully active can increase damage the following year.

Forests managed by local governments contained 1,734,013 infected trees this year, or 97.8% of the total, but their control rate was 61.9%, below the 99.9% rate in forests directly managed by the Korea Forest Service. Yoon said cities, counties and districts averaged just 0.87 staff members dedicated to forest pests and diseases, making it difficult for local governments to meet growing demand for control measures on their own.

The Korea Forest Service's initial national budget this year increased by just 0.05% from last year. Budgets for major control programs, including preventive tree injections and tree-species conversion, were also not increased.

Yoon warned that infected trees left untreated this year could lead to forest damage next year and called on the Korea Forest Service to expand its budget. He urged the allocation of contingency funds and specialist personnel to understaffed local governments and the establishment of a nationally accountable control system.