This might be a lenghty one. Still, i request you to read this in leisure.

 

The root of the solution: Vetiver (in Tamil, the word means 'dug up root') grass plants, vetiveria zizanioides have long been known to provide economical protection against soil & water loss and more recently they have also been found to be useful for water purification. However, the bone of contention is, while other nations have rapidly embraced it, in India its adoption remains rare.

In 1987, noting that soil erosion is the most serious agricultural problem in the world, Richard Grimshaw and John Greenfield, two agricultural scientists of the World Bank decided to it tackle on war footing. During their visits to India, they chanced upon the solution in a village near Gundlupet in Karnataka. "We learnt from these farmers that they have been successfully growing vetiver against soil erosion for centuries. It reduced rainfall runoff by as much as 70%, recharged groundwater (villages that use vetiver have much higher water levels in their wells), and improved ephemeral stream flow."

In the hilly terrains where tea is grown, soil erosion is a big problem. The tea estates didn't have permanent soil and water conservation measures. As such, during replanting, a lot of expenditure has to be incurred for this. In the past, one has to construct stonewalls (revetments) across the slope. Depending on the gradient, normally two or three walls (top, middle and bottom) were needed. On an average, stone revetments for a hectare of tea garden would require 350 man-days. Instead, 100 man-days would be sufficient if you opt for vetiver hedges."

Subsequent studies prompted the World Bank to launch The Vetiver Network (TVN), which has been disseminating vetiver technology to the world with a missionary zeal. Now there are more than 20 vetiver networks in the world and newer ones are being formed every year. In China alone, vetiver is so popular that the country now has a Chinese Vetiver Network and 6 corporations for the implementation of vetiver systems for environmental protection.

Best candidate for 'earth repair: What makes vetiver so popular? It's perennial and requires minimal maintenance. It's both xerophyte and hydrophyte. Once established, it can withstand drought, flood and water logging. It will grow in all types of soil regardless of fertility, pH or salinity. It is highly tolerant to toxic levels of aluminum, manganese, arsenic, cadmium, chromium, nickel, copper, mercury, lead, selenium and zinc. It will grow in a wide range of climates, survives in areas with average annual rainfall between 200 and 6000 mm and with temperatures ranging from 1° to 45°C. When drought, flood, pests, diseases, fire or other adversity destroys all surrounding plants, vetiver will remain to protect the ground from the onslaught of the next rains. It has a strong fibrous root system that penetrates and binds the soil to a depth of three meters and can withstand the effects of tunneling and cracking.

 

The vetiver system is low cost and extremely effective system for soil and water conservation, pollution control, wastewater treatment, mitigation and prevention of storm damage and many other applications. Vetiver can be used in the tropics and semi tropics, and where there are hot summers, and winters that do not include permanently frozen soil conditions. The roots of the grass have an average tensile strength of Mpa 75 (one-sixth the strength of Mild Steel), and improve the shear strength of soil by between 30 and 40%.

Crutch for rain-fed farmers : Richard Grimshaw, recalls "When I was introducing the vetiver system in areas, I introduced it by saying 'We have a technology that can improve your yields by 15-50%, that is permanent, once established, costs nothing and will drought proof your crops'. Then I go on with the explanation of how vetiver hedges conserve runoff and increase the moisture in the soil. Farmers are not interested in spending money on "soil conservation". No need to mention that vetiver hedges providing moisture conservation are preventing soil erosion too!"

A bund diverts runoff to drainage, thus denying the rain-fed farm the full benefit of the rainfall it gets. Whereas the vetiver hedge holds the rainfall back, spreads it out and gives it a chance to soak in to the ground as stored moisture. Excess runoff filters through the hedge and carries on down the slope at greatly reduced speed, but wetting all the ground as nature intended it to do." "In a particular case," he recalls, "the farmers had planted their Ragi, received six millimeters rainfall, enough to germinate their seed but then no more rain for over a month, the seedlings died. Their neighbors who had planted vetiver hedges retained enough moisture in the soil to carry their plants over and produce very good yields."

Vettiver can check weed invasion too. It can block the spread of other grasses including the world's worst creeping grasses. In Zimbabwe tobacco farmers reportedly plant vetiver around their fields to prevent invasion of other tough grasses. In Mauritius sugar cane growers rely on vetiver to prevent Bermuda grass from penetrating their fields from adjacent roadsides. Obviously establishing vetiver hedges along the periphery of tea fields could prevent invasion of deep rooted tough grass weeds. "

Water purification: It is recently discovered attribute of vetiver as its capacity to purify water, and thus to help in wastewater treatment. Vetiveria zizanioides, a species widely present in India, can absorb many heavy metals, nitrogen and phosphorous from water. In studies conducted in China using vetiver to treat effluents from piggery farms, the results were quite encouraging. Using vetiver to purify water bodies is easy, too. Being hydrophyte, the plants don't require a separate medium to grow in water. The only arrangement required to make vetiver plants survive in water properly is a float to maintain the balance between roots and shoot and to make the plant stand erect. Cut pieces of bamboo make a good float.

TVN has been awarding certificates to individuals who have been doing good work and demonstrating a high level of knowledge in specific areas of the vetiver System technology. Only one person from India Mr. Haridas, to get this recognition so far, and is one of 14 persons from around the world.

While more and more countries are embracing vetiver technology, it is quite ironic to see that in India itself, vetiver is a sort of 'touch me not' plant, despite having its origins here! A few months ago, a report in English daily stated that upon hearing a success story of railroad stabilization in China courtesy vetiver, Konkan Railways approached the railway authorities of China to know more about this while the technology has in reality originated from our own country. The link with soil conservation is also a strong motivator. "To get the water stored properly you need a medium, which is the earth - hence our soil too has to be protected from erosion. Let us work on SOS (Save our Soil)".

 

For further information do visit http://vetiver.com