Workers prune the male branches of cypress trees at the Temple of Earth Park in Beijing. Photos: VCG

Northern China has entered a high-risk period for autumn pollen, with health and weather authorities warning that pollen levels will remain high in many areas in early September.

The National Health Commission and the China Meteorological Administration on September 1 jointly issued the country's first pollen concentration forecast notice for autumn, according to a report by the People's Daily.

The notice said that most parts of northern China will see sunny to cloudy weather over the following week, creating favorable conditions for pollen production and spread.

In early September, pollen concentrations were forecast to reach a high level in northeastern parts of Northwest China, most of Inner Mongolia, central and northern parts of North China, as well as northern Henan. Central and western Inner Mongolia were expected to reach a very high level. 

A pollen protection advisory sign stands at the Temple of Heaven Park in Beijing.

Seasonal condition

Beijing has also entered its autumn pollen season. The Beijing Municipal Forestry and Parks Bureau said herbaceous plants in the city have gradually entered their pollen release period, with September expected to be the peak month for autumn pollen.

Ma Jun, director of the Institute of Public and Environmental Affairs, told the Global Times that the recent rise in pollen levels across northern China is closely linked to current weather conditions.

Sunny to cloudy weather, sufficient sunlight and suitable temperatures help wild herbaceous plants produce and release pollen, while relatively dry conditions also make it easier for pollen particles to stay suspended in the air and spread, Ma said.

Different weather conditions can have very different effects on pollen levels. According to Ma, sunny and dry weather usually helps plants release more pollen. 

Moderate winds can carry pollen through the air and allow it to travel over longer distances. Rain, by contrast, usually helps remove pollen from the air, temporarily lowering pollen concentrations.

Wang Bin, chief physician of the respiratory department at Wangjing Hospital of the China Academy of Chinese Medical Sciences (CACMS), told the Global Times that late summer and early autumn are common high-incidence periods for respiratory allergic diseases caused by plant allergens in northern China.

Common allergenic pollen during this period comes mainly from wild herbaceous plants, including Artemisia, Humulus and ragweed, Wang said.

Pollen allergies can affect both the upper and lower respiratory tract. Common symptoms include allergic rhinitis, throat discomfort and allergic asthma. Some people may also develop allergic conjunctivitis, itchy skin or other allergic reactions, he said.

Wang said reducing exposure to allergens is the most important step for people who already know they have pollen allergies.

During periods of high pollen concentration, they should try to limit long periods of outdoor exposure and wear masks when going outside. People with obvious eye allergy symptoms can also use protective eyewear to reduce direct contact with pollen.

Wang suggested that people who repeatedly develop allergic symptoms during the same season should identify their specific allergens when possible, so they can take more targeted preventive measures.

Workers clear away overgrown weeds at the New Town Binhe Forest Park in Beijing's Changping district on August 29, 2026.

Source control 

People with a history of allergic rhinitis or allergic asthma should pay particular attention to changes in their symptoms during the pollen season. Those who develop obvious wheezing, chest tightness or other serious respiratory symptoms should seek medical attention, Wang added.

Notably, Ma warned that thunderstorms during the pollen season can create a different kind of risk.

While ordinary rainfall often helps reduce airborne pollen, thunderstorms can sometimes increase the risk of acute asthma attacks. 

Strong air currents can lift pollen particles into the atmosphere, while high humidity may cause some pollen grains to absorb water and break apart, releasing much smaller allergenic particles.

Downdrafts during thunderstorms can then carry these particles back toward ground level, where they may be inhaled deep into the lower respiratory tract.

Under certain conditions, this can lead to a sudden rise in asthma cases, a phenomenon known as "thunderstorm asthma," Ma explained.

Beijing has also stepped up efforts to reduce allergenic pollen at the source.

The Beijing Municipal Forestry and Parks Bureau said the city began making preparations in late June and moved ahead with the removal and management of wild allergenic plants before the main pollen release period began in early August.

In heavily used areas such as urban parks, residential communities, schools, hospitals, office districts and major roads, workers have used a combination of phased cutting and uprooting to reduce pollen-producing plants without clearing large areas of vegetation at once, which could leave bare ground and create secondary problems such as dust.

In suburban parks, ecological forests and along transport corridors, mechanical cutting and weed crushing have been used to reduce flowering and pollen release. Plant waste produced during the work is required to be removed on the same day and properly disposed of, both to prevent pollen from spreading again and to reduce the risk of fire.

Looking ahead, Ma said parts of northern China are likely to remain in a high pollen period during September if sunny weather continues. The timing of the pollen peak can vary by region, with higher-latitude areas generally entering the peak earlier, while areas farther south may see a later and sometimes longer pollen season.