Great Challenges, Great Opportunities
This appendix highlights some environmental horrors and points to the role vetiver might play in alleviating them.1 The examples are presented to stimulate exploratory trials in those parts of the world where such devastating problems exist. Whether vetiver will work in sites like these is far from certain. In some, the plant will meet its greatest difficulties in just surviving. In a few, it may survive but fail to be effective. Nonetheless, it is a testimony to the potential inherent in vetiver that a single species could even be considered for such an array of challenging situations. Also, it is a testimony to the potential inherent in their green lines of grass that solutions to so many seemingly intractable problems can even be envisioned. Where vetiver fails, alternative species that make dense hedges should be sought.
Opposite: The deep soil here could be producing a lot of food, forage, or perhaps forests, but instead is being inexorably lost. Ideally, runoff pouring from the land behind should be deflected and dispersed far above this site. (That might well be done using vetiver hedges.) However, it is likely that the landowner will opt instead to merely try to stop this gully from worsening. (Indeed, it is a measure of the expense or ineffectiveness of the better known techniques that erosion has been allowed to progress so far on this valuable property.)
For such a task, vetiver seems very suitable. Starting at the head of the gully, lines of the grass can be planted from left to right. The lines should be spaced several meters apart and each should begin at a level several meters above the bottom on one side, run across the gully, and up to the same level on the other side. Once established, these grassy barriers will check the force of the rushing runoff and stop the silt from leaving the site. Through the years, a series of stable terraces will form, eventually resulting in an almost rounded depression that can be grassed and then grazed or safely planted with trees.
This particular location in rural Australia is not in vetiver's prime geographic zone; however, countless similar scenes can be found throughout the hot regions where vetiver thrives. (Photo: Australian Academy of Science)
Overleaf: When watersheds are degraded to the point where they no longer absorb torrential rains, property can be destroyed and lives lost even at a great distance. With deforestation laying bare more and more of the world's sloping lands, flooding is an increasing hazard to everyone. Rushing runoff can pour into the lowlands with a power beyond stopping even in city streets.
Protecting vast watersheds with thousands of vetiver rows might well seem nigh on impossible, both logistically and financially. However, compared to conventional berms, bunds, and terracing, such grassy dams may be practical on a wide scale. Massive efforts would certainly be required, but this could well pay off many times over if it prevents a single incident like the one shown here in Hong Kong. Cities (or maybe insurance companies) might well find it in their interest to stimulate the necessary vetiver plantings on the faraway hills. (Photo: Hong Kong Government Information Services)