It takes strength, skill and, most importantly, intellect to be a bamboo artist, erecting intricate webs of sky-high walls and platforms strong enough to hold a legion of construction workers.
In Hong Kong - the last frontier of bamboo scaffolding - where tall, skinny buildings shoot up daily, more than five million bamboo rods, each six to seven metres long, are used every year by the construction industry.
But the future of the bamboo business remains precarious, due to a lack of new blood and the diminishing supply of the raw material - which is both cheaper and less destructive than metal alternatives.
But for master scaffolder Li Fuk-yin and his colleagues, Anson Yan and Lau Co-on, it is a profession like no other.
Watching the trio deftly clamber up a bamboo pole to fasten one more attachment to the growing web, one can only wonder how many years of training it took to learn how to build a structure out of bamboo.
"Sky-high bamboo scaffolders in Hong Kong", Video by Hedy Bok
"It's not just learning to tie bamboo together securely. Most of the time, it's knowing the physics and the laws of weight," explains 32-year-old Lau, who has been a scaffolder for six years. "Most of the training is actually learning to build [bamboo platforms] that are safe and strong enough to hold construction workers in all the different imaginable sites."
All three skilled scaffolders work for a maintenance-related firm, often toiling during unsociable hours, always with a cigarette between their teeth.
Yan, 31, the youngest and least experienced of the trio who is a father to two children, is responsible for tasks such as measuring and cutting bamboo. Li, 39, who has been a scaffolder for over a decade, is in charge of the bigger picture. It's his job to design the overall structure.
"The hardest ones [to build] are for big hanging neon signs over streets," said Li. "It's hard to build round it and [you can't have] an anchor straight down."
Jobs, both big and small, come in regularly - in Hong Kong's concrete jungle, bamboo scaffolding is sometimes the only option for many maintenance jobs. Workers can cut and shape the relatively nimble material around the city's densely and closely built maze of buildings.
For Lau, the bamboo business is more interesting than other construction jobs. But, he says, come the summer months when the temperature soars, working in the hot heat can be gruelling. Scaffolders often have to work when the city sleeps in the small hours of the night.
Lau and his colleagues are part of a diminishing profession. Currently, there are 1,751 registered bamboo scaffolders, according to the Construction Workers Registration Board, and roughly 200 scaffolding companies are operating in the city.
But government policy has made people reluctant to join the bamboo business.
"In the past, we got people into the industry by word of mouth - through a relative or scaffolder friend. It helped to have someone they knew who they could be apprenticed under," said So Yu-hang, who is director of Wui Fai Holdings, a member of the Hong Kong and Kowloon Scaffolders General Merchants Association, and scaffolder for over 30 years.
"Now, most [new recruits] will have to undergo training with the Hong Kong Construction Industry Council [for their licence]. It is particularly tough as [the young people] won't have as much hands-on experience, even if they get their licence."
The CIC conducts year-long free bamboo scaffolding training for teenagers and a 100-day course for adults.
All trainees must take the Intermediate Trade Test and gain their licence. New recruits earn as little as HK$350 a day, while old hands can make around HK$10,000 a month.
Staffing is not the only problem. Despite its unique advantages as a scaffolding material, quality bamboo is also getting harder to find, said So.
Over recent years, the number of bamboo importers have dwindled to just a handful.
Originally, bamboo - which after three years matures to a naturally wide diametre and thick skin perfect for scaffolding - came from the Xiaoxing area in Guangdong. But over the past two decades firms have had to look to Guangxi and Guilin , said So. The industry's fear is that one day supplies will be blocked for environmental reasons and export embargoes. Attempts to import bamboo from Thailand or switch to synthetic or plastic bamboo have so far proved unsuccessful.
So recalls an episode a few years ago, when the Berlin government invited a team from his firm to an industry conference.
Hong Kong's bamboo aficionados were treated more like artists than construction workers, as they crafted an entire covered stage for the German delegates.
But in Hong Kong, So says, people see bamboo as a backwards material in a hyper-modern environment - they are often baffled by its popularity.
"[Bamboo scaffolding] is a traditional industry, so there aren't too many rules," said So. "The strength of bamboo is often measured just by the eyes of experienced scaffolders, and tested using our body weight."
So feels that his profession has often been misunderstood. "It's been taken as a low-class profession, and often portrayed as extremely dangerous," he said.
Last year, there were 24 construction accidents - just three of which involved a person falling from bamboo scaffolding.
"To be honest, accidents are unlikely if a companies provides up-to-scratch safety gear for their workers, and are diligent in safety checks," said So.
In the event of a scaffolding collapse, iron rods would cause a lot more damage than the much lighter bamboo ones, he added.
"We are proud of what we do. It's an ancient trade, which is extremely useful, but it's also a form of art," he said. "There aren't places which still use bamboo scaffolding like we do in Hong Kong - not even in China.
"If we don't appreciate the skill and knowledge, it will one day disappear."