where there is a vetiver hedge. In China, a farmer planted vetiver grass around his pond: within six months it had formed an almost impenetrable hedge that not only corralled his ducks but also provided fodder and mulch.
Not the least of these observations was that vetiver can grow in an amazing range of soils. In fact, the plant seemed to thrive so well in adversity that it was hard to find a place where it would not survive. Even in quartz gravel, with little fertility, Greenfield was able to make it grow, after a fashion. And, most impressive to a plant scientist, in Sri Lanka some vetiver grows in bauxite, a material that is toxic to almost every other species of plant. (The farmers there actually used crowbars to plant the vetiver into solid bauxite.)
It can grow in an amazing range of climates as well. Both Fiji and central India lie in the monsoonal tropics, but soon it became clear that vetiver could grow in many other climes. In India, for example, it is found in the rainforests of Kerala, the deserts of Rajasthan, and the frost zones of the Himalaya foothills. (It is even found near Kathmandu in Nepal.) It occurs on some coasts, growing in the direct path of salt spray. All in all, it seemed that vetiver grass could thrive under very wet (more than 3,000 mm) and very dry (less than 300 mm) conditions, and perhaps everything in between.
Vetiver also proved well adapted to temperature. It thrives in Rajasthan, where temperatures reach as high as +46°C, and it survives in Fujian, China, where winter temperatures have reached -9°C. It is certainly surprising that a tropical grass can withstand such cold, but one enthusiast even planted it on a ski slope in Italy, and there, north of Rome, it has (perhaps miraculously) made it through several winters.
With all these discoveries about a species almost unknown to the world, it is not surprising that Greenfield and Grimshaw were enthusiastic. Eventually, through word of mouth and the World Bank's Vetiver Newsletter and its handbook, Vetiver: a Hedge Against Erosion, others also were caught up in the fervor. Indeed, the excitement surrounding vetiver grew so much and the implications of using it seemed so astounding that many outsiders queried the sincerity (not to say sanity) of those who were discussing it with such zeal.
It was the skepticism surrounding the extravagant claims about the plant that led to this report. The World Bank, the U.S. Agency for International Development, and the U.S. Soil Conservation Service asked the National Research Council to evaluate the claims, the practical reality, and the implications behind the vision of John Greenfield and Richard Grimshaw.
The rest of this report highlights our findings and conclusions.