Driving through the dustier districts of South India, such as Kolar or the northern interiors of Tamil Nadu – you often pass clumps of the paddle-shaped cactus known as Opuntia or Prickly Pear. It grows wild though is often used to demarcate the boundaries between fields. It looks so rooted in the ancient landscape that it can be a surprise to learn that it an import from South America.

The emu farmers of Erode would be familiar with the cactus. It inhabits the same dry terrain that was said to be ideal for raising the large flightless birds from Australia. The terrain, in fact, was what changed the idea of raising birds with no proven market in India from dubious to alluring. When your land only supports low value crops, like millets, the idea that an investment of Rs1 lakh in emus could bring you returns of Rs3.34 lakhs in just two years can sound distinctly attractive.That was the promise made by promoters like M.S.Guru of Susi Emu Farms.

It was backed by promotions using Tamil film stars and questions about where the market for the birds was were brushed aside. Emus were total value animals, the promoters said, since the meat had gourmet and health appeals (tastes like beef with lower cholesterol), the skin made high quality leather, the feathers and eggshells could be used into handicrafts and, as a special appeal, emus had a gland that yielded an oil with considerable export value.Details about where exactly the oil would be exported to, and who the consumers would be, were vague, but no one probed too deeply, including the many journalists drawn by photographs of farmers in lung is feeding birds almost as big as they were.

In almost no time there were around 250 emu farms in the state, mostly around Erode, with over 12,500 birds. Guru’s company was talking about setting up a chain of emu restaurants across the country, with the first one outside the South recently opening in Delhi.What happened next has been well documented by ET and other media. Guru and other promoters have vanished, taking with them investments running into hundreds of crores, made by an estimated 36,000 people, according to a statement put out by chief minister J.Jayalalithaa’s office. The birds left behind were starving, forcing the state to step in and pay over Rs3 crores to take care of them for three months. The birds will now be culled – though animal rights organisations are protesting – at a considerable cost, with not much prospect of recovering the expense through sale of meat, since it turns out that few really want it, or any other emu products.

Emus in Tamil Nadu, it turns out, were a Ponzi scheme of the kind the state is notorious for (chit funds, teak, goats are past examples), given added appeal by its use of arid land. There seems, in fact, to be a whole series of products that are sold with the promise of realising high returns from arid land, such as biofuels like jatropha and jojoba, agave (a cactus-like plant used to make tequila and a sweet syrup) and perhaps even the current boom commodity of guar beans.These all seem to find receptive audiences in desert-land farmers, who generally have larger plots than those in more fertile areas, and less of an incentive to stick to established crops.

Quite often there are government schemes available too, offering cheap loans for semi-arid crops. So the farmers take a gamble on these products, and sometimes they do make short term profits, because these are not all scams. Yet they are sold on extravagant promises of transformational prosperity and long term yields, which they almost never deliver.And this is where that cactus comes in, as a visible reminder of the first such desert dream sold in South India. Opuntia first came to India as part of a scheme to produce cochineal, a red coloured dye derived from insects that feed on the cactus. Cochineal has been produced in Latin America for centuries, by people like the Aztecs and Incas. And when the Spanish arrived they quickly realised the value of the dye, since it holds fast to cloth, and produces two different, desirable shades – brilliant scarlet and darker crimson. It is also safe for consumption, which is why cochineal has been used to colour cakes and drinks like Cherry Coke (though substitutes have been found as vegetarians became aware of its use).

Arvind Sinha, in an essay on cochineal cultivation on the Coromandel coast, published in Coastal Histories: Society and Ecology in pre-Modern India, writes that by 1736 880,000 pounds of cochineal were being imported into Europe – and around half a million pounds sterling were being paid to the Spanish, who had a lock on the supply. These figures come from the dispatches of the Court of Directors of the East India Company, which showed that they were aware of the potential profits of finding their own source of cochineal.

And in Dr.James Anderson they found the man to make it happen. He had held posts like Physician-General to the Madras Army and Chief of Hospitals in Madras, but he also served, like most doctors at that time, as an unofficial scientist-at-large, while also, like most British officials in India at that time, looking out for ways to make a fortune. Cochineal came to his attention and he started looking for Indian insects that could produce such a dye. In 1786 he thought he found one, and sent samples back to Britain, but it proved to be impracticable for dyeing.But this initiative put Anderson in touch with scientists, like the botanist, Sir Joseph Banks, who pointed out that rather than trying to find an Indian bug, he should try growing the original.

The climate in parts of South India was similar to the semi desert areas where cochineal bugs came from and, equally important, cheap labour was available for the painstaking job of harvesting the bugs (a British initiative to grow cochineal in the West Indies had failed for lack of labour). Anderson was so charged by the idea that he became an evangelist for cochineal, promoting its growth not just in India, but in desert parts of British colonies around the world.In India Anderson experimented with local plants, but finally decided that it was best to get Opuntia.

Botanists like Banks sent specimens, and by the early 1790s Anderson had over 2000 plants in a plantation near Rajahmundry. The problem was now getting enough insects to establish a breeding population, which was not easy since they had to survive a long and damp sea voyage. Anderson wrote letters begging for help to the Company Directors, who were responsive, but didn’t want to antagonise the Spanish. Sinha quotes one source on how the Directors “did not intend the instructions relating to the care and preservation of the cochineal insect at sea should be made public…”Finally in 1795 Anderson appeared to have some luck.

A British ship captain named Neilson, who had earlier been based in Madras where he had encountered Anderson and his obsession, docked in Rio de Janeiro and on a walk outside town he found a cochineal plantation. He smuggled out some samples, and sailed with them to Calcutta, by which time only one leaf, with a few dozen insects had survived.

But with just this, writes Victoria Finlay in Color, her wonderful book on the histories behind colours, “top men at the East India Company started imagining their fortunes were made.”In a letter to one of the British governors, Anderson laid out the basic desert land dream: imagine, he wrote, “the opportunity of converting the most waste, barren and dry lands in your possession to great advantage, by encouraging the cultivation of the plant.” And initially it seemed to work. By 1797 the Madras government had collected 21,774 pounds of cochineal, and Anderson must have started imagining his fortunes rolling in.

But unfortunately it turned out that they had got an inferior version of the bug (the same problem was to affect the vanilla boom in Kerala some years back) and Anderson never got the returns he was expecting.The real death knell for Indian cochineal was sounded a couple of decades later when chemists like William Henry Perkin synthesised vivid dyes from substances like coal tar. Chemical dyes were cheap and easy to produce in bulk and quickly drove organic dyes like cochineal into niche markets (like luxury use) which were easily supplied by existing South American production.

In recent years, there has been increased interest in natural cochineal, but no one seems to be – yet – trying to grow it in South India, where the descendants of Anderson’s Opuntia plantations now grow free.This is how it always seems to go with arid-region crops.

Take guar, which for years had a small, stable market for the edible gel produced from it, which is used in products like cakes and ice-cream. When it was discovered that the same gel could be used to stiffen the water used to force out gas trapped in rock formations – the process known as fracking – demand exploded, aided by canny speculators who, as Sugata Ghosh wrote in ET, correctly saw how they could take advantage of the ignorance of the many less experienced commodity traders who had recently come into the market.The result was that in March this year guar futures shot from Rs3000 a quintal to Rs25,000.

Most of these profits are, of course, going to speculators, but Indian farmers, who grow 90% of the world’s guar supply, are also happily reaping benefits. Yet this is a market that is sustained by the fact that fracking is still in its nascent stages, when people are still figuring out the technology and can afford to pay higher for existing options like Indian guar. Yet if fracking really takes off, the chances are that alternate gels will be devised, or that cultivation in other arid places will shoot up, and prices will drop. There is money to be made in guar now, but long term fortunes are unlikely.If potential alternatives are one problem, the limits of arid-land production are another. Despite their rock-solid appearance, most semi-desert lands are actually very delicately sustained ecosystems that can easily crash when over-exploited. This seems to have been one of the problems with jatropha, whose oil-bearing seeds never seem to have been produced in amounts sufficient to make their use as bio-diesel viable.

This year has already seen a drop in guar returns – one reason, paradoxically, for the soaring price – and as cultivation expands the ecosystem in which it is grown will see increasing pressure and diminishing returns.But perhaps the biggest problem is developing markets for these products. As with emu meat, it turns out that people generally don’t want these desert products, other than perhaps small niches. Agave, for example, has been promoted in recent years as an ideal arid-region crop – again, the Deccan is compared to interior Mexico, where it comes from – from which tequila and honey-like agave syrup could be derived.

An Indian-made tequila, happily named Desmondji, is now available in Goa, made from Indian agave.Desmondji could do well in Goa, which provides a perfect environment of low taxed and easily available alcohol, a constant stream of young vacationers who don’t need much persuasion to do tequila shots and foreign tourists who might find novelty value in taking home a bottle of Indian-made tequila (it probably helps that the local alternative of cashew-fruit based feni tastes vile). But none of this means that Indian tequila will work at a national level, where it will run into the insanity that is national-level liquor distribution. There is also no evidence that Indians are queuing up to drink tequila – and if they were, you can be sure that importers would flood the market with cheap Mexican tequila that, even as an inferior product, would undercut the Indian one (this is exactly what is happening with wine).This is not just an Indian story. Emu investors would have done well to check out the global history of farming ostriches and emus.

In his fascinating book Dreambirds, South Africa born Rob Nixon traces a long history of short booms, scams and failed schemes involving ostriches. It stretches from the Karoo, the desert area in South Africa where he was born, where at the start of the 20th century a city called Oudsthoorn was briefly one of the richest in Africa, because of its trade in ostrich feathers, which were used in women’s hats, and also the helmets of British colonial governors.But ostrich plumed hats, and colonial governors, went out of fashion, and the Karoo has never regained its prosperity, though ostrich farms still produce the birds, mainly for the meat which has always been consumed in a small way in South Africa.

Nixon then picks up the trail more recently, in the American Southwest where, in the mid 1990s, he finds an ostrich boom taking place, as an unexpected side-effect of the anti-apartheid movement. This lead to an embargo on South African products, including the ostrich leather, which has an odd pock-marked appearance, but which was popular for making the boots that were a basic style item in places like Arizona and Texas.

As boot manufacturers desperately looked for alternate sources of ostriches, some realised that they could be raised right where they were. And this lead Nixon to the American Ostrich Association’s annual meeting in San Diego where he encounters egg incubators called Mechanical Ostrich Moms (MOM), specialised ostrich farming software called HITSS (Head in the Sand Software) and microchips that can be implanted in the birds to deal with the emerging issue of ostrich stealing. It all makes the Erode ostrich promoters seem like rank amateurs.

Yet when Nixon attempts to question one of the ostrich evangelists with stories of past big bird booms in South Africa or, he later discovers, even in the American Southwest, he’s brusquely dismissed: ” ‘No need to talk about that here,’ he said. ‘That’s ancient history.'” And that, it seems, is how it always goes. No matter what busts and crashes have happened in the past, there always seems to be a new miracle product, a new scheme, a new gamble, because the one thing in which deserts are endlessly fertile is dreams.

vikram.doctor@timesgroup.com