Under Li Yanhong's expert touch, rough birch bark is meticulously peeled off before being separated into up to 40 layers, each of a different tint. Switching between a pair of scissors and a carving knife, the artisan from Bailang town, Arxan in the Inner Mongolia autonomous region, adeptly cuts, folds, pastes, twists and carves the paper-thin layers into different shapes and sizes.

She then mounts them to create a simple, yet elegant bark picture.

Because of the differences in pigmentation between its outer and inner layers, birch bark produces dozens of hues, from silver gray, ash white and off-white, to brownish yellow, pink gold, gray-green, gray orange, and earthy yellow.

"At the same time, it has dense fibers, and a seamless texture, and layers as delicate as paper, which makes it an ideal material for art," Li says, adding that the bark is also waterproof as a result of its oil content, which makes her creations durable. "The best-selling part of my art is that its rich natural colors won't fade away."

With the arrival of winter, Li and her team have been busy producing the distinctive local art for tourists. "They are wildly popular with travelers, especially young people," Li says excitedly.

Her pictures primarily use bark from birch trees; its natural colors and textures are the foundation of her designs.

The art form was devised a long time ago by Arxan's forestry workers and has since evolved to draw on the principles of traditional Chinese composition.

"The unwanted bark from trees is transformed into something valuable in our hands. It's eco-friendly, green, and never fades," says Li, in her 40s.

Li usually starts collecting bark in the summer, when the temperature is just right for exploring the forest. "It would be too cold in spring or winter, while fallen leaves would get in the way in autumn," Li explains, adding that she chooses smooth bark with light texturing, with which it is easier to work.

Turning bark into fine art requires a deep understanding of its properties. "You need to control your strength when peeling away the layers, one by one, without breaking any of them," Li says.

In order to bring the local elements that feature in these pictures to life, such as sika deer, artisans need to observe closely to breathe soul into their work. "Everything requires time and patience," Li says.

It usually takes a beginner at least six months before they can make a simple picture.

"The colors in bark are like human fingerprints, and no two pieces are the same. The distinctions grow as the bark oxidizes, a process that varies with the time it takes to make a piece," Li explains.

Born into a forestry worker's family, Li developed a connection with bark art as a child. Surrounded by dense forest, she would go out with other residents to collect fallen bark to make everyday items like cigarette cases and containers.

She often watched women making bark pictures to decorate their homes, or to make as gifts for friends and family. "I was especially attracted to the layered texture and gradating colors of birch bark," Li recalls.

Whenever her grandmother and aunts were working on a piece, the young girl would help, working her way up to creating her own first designs, images of court ladies or cartoon characters.

After finishing a course in tailoring at a vocational school in Ulanhot, Inner Mongolia, about a four-hour drive from her home, Li began working at a clothing factory, where she earned just enough to make ends meet.

Whenever she had the time, she would return to her childhood hobby and make bark art, which to her surprise has been growing in popularity as a souvenir since the 2000s, as increased forest protection efforts have given rise to flourishing tourism.

"Initially, I earned just a few thousand yuan a year, but over time that grew to 7,000($967) or 8,000 yuan, which made a big difference to my family income," she says.

In 2017, Xie Caiyun, who ran a bark-picture production business in Bailang town, approached Li and persuaded her to return to the town and help residents upgrade their art as a means of alleviating poverty.

Li accepted Xie's offer to work at the company, which she says was one of the best decisions she ever made.

At the end of 2018, bark art craftsmanship was named a form of regional intangible cultural heritage in Inner Mongolia, and support for its development began to flow.

Li still remembers that there were only a few makers when she first returned to the town and that experts from the Beijing Institute of Fashion Technology were invited to give her and other artisans art training in 2019.

"From technique innovations to color matching, from integrating art styles to the use of materials, the training gave us the confidence to experiment, broadened our thinking, and expanded our horizons," Li says.

Li was inspired to incorporate other crafts, such as cloisonne and filigree work, in her pictures. For instance, she has used cloisonne to create headdress for figures, and has made earrings and fridge magnets with bark.

"In the past, the work ended with the picture itself, but we have found we can present pretty much anything through bark to cater to modern needs, such as items of home decor," Li says.

Li's forest folk culture business has continued to develop, for example, making Peking Opera facial masks and Chinese zodiac series, which are among the most popular.

The increased diversity of bark pictures has boosted sales and encouraged more people to take up the art.

Li even talked Zhao Guihua, now one of her colleagues, into picking up her childhood art again two years ago.

Under Li's guidance, Zhao's skills have improved significantly. The woman's initially somewhat rough creations have now become refined works of art, earning her the title of first-tier master at the company.

"I used to work at a water plant, earning at most 20,000 yuan a year," says Zhao, who is in her 50s.

"Making bark art pays more, and I also have flexible working hours, which is much better than before," Zhao adds.

So far, Li has helped change the lives of 20 formerly impoverished women.

"We rank artisans by their skill levels, from first-tier master to second-tier master, down to junior instructors," Li says.

Orders are completed on a piecework basis, with production times ranging from several days to several months, depending on the complexity. High earners make an average of 4,000 to 5,000 yuan a month.

At the eighth China Intangible Cultural Heritage Expo in Jinan, Shandong province, in October, Li and her co-workers' pictures were a big draw.

"Many museums have shown interest in buying our work or in selling it for us," says Jia Zhiling, a manager at the Bailang forest culture company.

Earlier this year, bark pictures made their way to the United Kingdom and Ireland for the Chinese Lunar New Year celebrations, Jia says.

Li has also come up with kits for amateurs to enjoy a taste of the art form's beauty.

"It has been a hit with travelers, especially those on learning tours," Li says.

Looking back, she says that she is delighted that bark art has evolved from a record of life and work in the forests into one of the most popular local tourist souvenirs.

"It is a gift from nature. I will continue to infuse a touch of modern style into its authenticity," she says.

Contact the writer at yangfeiyue@chinadaily.com.cn