Another day draws to its end in Antanandavehely, a peaceful village on the eastern slopes of the Masoala peninsula, the largest nature conservation area in Madagascar. The last rafts, loaded with rosewood, pull into the river bank. As the loggers return, the atmosphere grows festive, infused with the smell of beer and the sound of dice clicking.

Among the russet logs, exhausted by a hard day’s labour, Blandine checks the weight of the incoming cargo. Wearing a little black dress and sparkling jewels, she is a go-between for the big businessmen on the coast. Dipping into a bag full of banknotes she pays $135 for a two-metre-long log, generally weighing about 120kg, a fortune in this poverty-stricken country. In addition to its rich colour and fragrance, rosewood is prized for its even texture and high density. It finds a ready market in China, where reproduction furniture is highly sought after.

At this price there is no shortage of willing hands, in Madagascar and China, to plunder forests on the Unesco World Heritage list and pack containers full of rosewood logs, to be carried along routes well oiled by corruption. One of the main routes takes the wood from the streets of Antanandavehely to prosperous Xianyou, a new town of 1 million people in Fujian province. Its journey passes through Zanzibar in Tanzania, Mombasa in Kenya and Hong Kong. There are certainly others but this is probably the largest, its ramifications reaching up into the higher echelons of Madagascar’s government. Everyone here knows about the racket in bola bola, as the wood is known locally. Many of those involved belong to old Chinese families, who arrived in the early 20th century to build the railway.

In February 2014 Madagascar’s new president, Hery Rajaonarimampianina, promised to take control of the battle against rosewood trafficking, but nothing changed. This was perhaps not unexpected. During his five years as finance minister illegal trade in rosewood soared.

More than 900km from Antananarivo, the capital of Madagascar, on the edge of the Masoala rainforest, the loggers seem unconcerned. In the hut that serves as home and office, the head of the Antanandavehely community Eric Mbita admits that alongside rice, vanilla, cloves and coffee, his fellow villagers live mainly on rosewood logging. In five yeas the population has risen from 1,200 to 1,800, swollen by migrants from the coast keen to cash in on the booming trade.

The village on the river Iagnobe is well placed for checking the timber that is taken downstream on makeshift rafts. Nothing gets by without being unloaded and weighed, sometimes stored for weeks in pits dug into the bank and carefully concealed. It takes five hours on a pirogue to reach the Indian ocean. The work is well paid. The rate for dragging logs to the river is 15,000 ariary ($5.60) a day, and for ferrying the timber through the rapids to the sea as much as 40,000 ariary ($15).

But those who labour at this level never become rich. Even the village teacher needs to supplement his income by logging. About 100,000 people live round the conservation area, which Unesco classified as being endangered in 2010. The illegal trade in rosewood has become their main source of income.

The oil-palm plantations of south-east Asia are associated with images of widespread devastation, but with rosewood the destruction is much more selective. Loggers will only fell a couple of trees per hectare, so it takes an expert to spot the damage.

But logging is gradually upsetting the natural balance of the rainforests. “To get one tree out, they have to cut everything growing round it, then clear a route to the river. The paths they leave open the way for other forms of trafficking, such as prospecting for precious stones, plentiful in Madagascar,” says Aro Vonjy Ramarosandratana, head of botany at the science faculty in Antananarivo and adviser to the Convention on International Trade in Endangered Species (Cites). Drawing on satellite images and field mission, his teams have mapped eight sensitive areas.

It was too dangerous for us to visit Masoala, but the scientific verdict is beyond doubt. “Outside the parks there are no longer any trees large enough to produce seeds. Inside, the largest trunks are only about 20cm in diameter. It takes 40 to 50 years to reach this size,” Ramarosandratana explains. In March 2013 his work contributed to classifying Dalbergia species, to which Malagasy rosewood belongs. Since then trade in this precious timber has been subject to an international embargo, which will only be lifted when the national government can frame an action plan that convinces the 180 Cites signatories. Last summer the embargo was extended by a year.

Illegally felled rosewood cut in Marojejy National Park, Madagascar. Photograph: Kevin Schafer/Alamy

The port of Antalaha, better known for exporting vanilla pods, has also long been associated with the rosewood trade. The day we visited, 300 logs lay in the sun outside the customs office. Down the road thousands of trunks littered the yard of the regional environment and forestry agency. In 2011, two years after the NGOs Environmental Investigation Agency and Global Witness published a damning report, the government issued a decree threatening illegal loggers with prison sentences of up to five years and heavy fines. Huge raids were organised but the decree was never put into effect. According to unofficial figures some 350,000 logs were impounded on government premises and in the forests. Part of this trove has since been stolen; some has been sold with corrupt customs officers turning a blind eye; either way freshly cut logs have replaced the missing timber.

In an attempt to make some progress on this issue, the World Bank has called in international experts to clarify the tangle of conflicting laws and suggest workable solutions. Slated for July 2014, the guidelines have still not been published. Meanwhile trade is still flourishing.

From his office at Cap Est – also known as Port Bola Bola – Emmanuel Ralaimampianina can watch the ships loading timber en route to China. “There is nothing I can do,” says the local Madagascar national parks representative. “We are not even empowered to issue a summons.” Along the undeveloped coastline between Cap Est and Cap Masoala there are five breaks in the coral reef, which enable ships to be loaded. “The biggest one is at Ifaho,” he explains.

Most of the timber leaving Madagascar now takes this route. In May Interpol tipped off customs officers at Mombasa, who seized 13 containers containing 420 tonnes of timber on the Kota Hapas. The Singapore-registered ship was heading for Hong Kong. It had stopped off at Zanzibar, after leaving the Malagasy port of Tamatave, with all the necessary paperwork. The timber was worth an estimated $13m.

Neither Zanzibar nor Hong Kong have translated the Cites regulations on trade in protected timber into law. This means that importers do not need to produce an export permit from the country of origin. Zanzibar has other advantages too: not only is customs duty minimal, but setting up shell companies is easy. But though investigators may waste time tracking down illegal traders, the real business is going on across the border.

In 2012 China officially imported 757,000 cubic metres of rosewood, registering 10-fold growth over the previous decade to cope with escalating demand and dwindling domestic supplies. The timber comes increasingly from Africa. Negligible quantities of Malagasy rosewood still appear in the official statistics but there is no record of any seizures of illegal imports in the port of Hong Kong.

In May 2013 Cites called on China to tighten up controls and a circular was sent to all the customs authorities. Timber importers also received a warning to stop buying Malagasy rosewood, but the message does not seem to have reached Xianyou. “We buy our wood on the basis of photos without any direct involvement in the dealings. Frankly, one needs to be on good terms with the customs officials,” says one furniture manufacturer, who claims to have 80 tonnes in his store.

Xianyou is booming, its skyline cluttered with high-rise buildings and cranes. But 9,000km away, on the other side of the Indian ocean, Madagascar is still racked by poverty, a prey to corruption and greed. A tiny minority is making a fortune from plundering natural resources. “All they think about is their filthy traffic with the Chinese. What will we do when we have no more forest and there’s no longer enough rain to water our rice?” asks a national park guide who has come up against the illegal loggers.

International pressure to condemn the rosewood trade has, nevertheless, been building since 2009. One of the most emblematic blogs on the subject, The Rosewood Chronicles, is written by someone who calls himself Hery Randriamalala.

Writing from an isolated spot in the rainforest, he draws inspiration from the place’s stupendous beauty. “We dreamt of justice. We imagined all it would take was to name them and shame would stop them. For the time being we have failed.”

This article appeared in Guardian Weekly, which incorporates material from Le Monde