Beijing addresses 'catkin nuisance'

Beijing's municipal authorities say they will not cut down the city's mature poplar and willow trees despite the annual "catkin nuisance", arguing that the ecological benefits of the towering trees cannot be easily replaced.

"Because of their outstanding advantages — fast growth, dense shade, strong carbon sequestration, and low cost — large-scale or onetime removal of mature poplar and willow trees is not feasible," said Jiang Yingshu, director of the science and technology division at the Beijing Municipal Forestry and Parks Bureau.

Jiang noted that trees with a diameter of 30 centimeters are typically 30 to 40 years old. Replacing them with saplings of five to six centimeters would take another three to four decades to achieve the same ecological impact, such as water and soil conservation. Instead of a blanket removal, the city is gradually replacing aged and weak female trees, which produce the fluffy seeds.

The catkin season in Beijing began on April 6 and is expected to end in late May.

In response, the city has launched a multi-agency action plan. Landscaping teams use high-pressure water sprays on tree canopies, followed by sanitation crews cleaning the road surfaces to create what the bureau calls a "closed-loop control system".

The city has established more than 100 monitoring sites to track the catkin cycle. Officials hold daily consultations with landscaping and meteorological experts, releasing forecasts through official channels and dedicated alerts.

To address the problem at the source, the city is collaborating with research institutions and universities. They have collected nearly 400 superior germplasm resources of low-catkin or catkin-free trees, resulting in 16 improved varieties and 100,000 cultivated seedlings.

Additionally, workers are using an environmentally friendly, nontoxic coagulant to form an "ecological film" on the canopies. Applied through high-pressure fog cannons or drones, the film reduces catkin dispersal by more than two-thirds for each tree. The substance degrades naturally under rain and sunlight.

Wu Di, a resident in Beijing's Dongcheng district, said the government should do more to communicate these efforts to the public.

"In fact, many of our concerns are precisely what these departments are already working on," Wu said.

"While taking practical actions on the ground, authorities must also proactively meet the public's right to know by providing clear explanations and thoughtful guidance," Wu added.