Vetiver Grass A Thin Green Line Against Erosion (1993) / Chapter Skim
Currently Skimming:
4 Questions and Answers
4 Questions and Answers
Pages 59-70
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 59... ...
They result from reviews and comments collected from a dozen experienced vetiver specialists and a dozen vetiver skeptics. Will Vetiver Stop the Loss of Soil?
|
From page 60... ...
The types of South Indian origin apparently produce nonviable seeds and must be maintained by vegetative methods. Luckily, this is the fragrant-root type that has been spread throughout the tropics.
|
From page 61... ...
The vetiver method contrasts with rock walls, dirt barriers, and other mechanical methods that hold, concentrate, or divert water off site. Vetiver supporters see this ability to keep the water spread out across the slopes as a major advantage.
|
From page 62... ...
Even in volcanic ash and sandy bottomlands, the task of digging vetiver roots is so difficult that it is often hard to find people willing to do it. Also, separating the soil from the intricate roots involves extreme drudgery.
|
From page 63... ...
Certainly in some cases (cotton fields laced by vetiver hedges in South India, for example) , no obvious edge effects are seen; the plants beside the hedges are as tall and productive as those elsewhere across the field.
|
From page 64... ...
For example: · Coastal sand dunes in South Africa. · Extremely acid soils (with pH as low as 4.0)
|
From page 65... ...
, but vetiver is currently the only practical species for low-maintenance, single-plant hedgerow erosion barriers. Although the vetiver found almost everywhere in the tropics is the same species, it has been scattered in myriad locations for a long time, and it is possible that the germplasm is not as genetically uniform as might appear.
|
From page 66... ...
This is the type now spread widely through the tropics. As previously noted, a second type growing wild in North India is flowering and fertile and produces seedlings under conditions of high humidity and high soil moisture.
|
From page 67... ...
to give a hedge a head start. As the critical mass of hedge builds up, the farmers obtain planting material from their own plots at no cost.
|
From page 68... ...
No. Whereas a gap in an earth bund is catastrophic because the impounded body of water pours through, a vetiver hedge is not a solid barrier and it need not be perfect to work.
|
From page 69... ...
Indeed, if a grass barrier is too palatable to livestock, it may lose its effectiveness. Animals are found almost everywhere in Third World countries, and wildlife or livestock will reduce an edible erosion barrier to ground level, especially in the dry season when feeds are in short supply.
|
From page 70... ...
Over the past 50 years, the main approach to worldwide erosion control has been oriented toward engineered systems, such as terraces, bunds, or contour drains. The use of vegetative systems is generally not attractive to conservation specialists trained in engineering techniques.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.