His Majesty the King has been intensely studying through the methods to solve soil erosion problems which caused damages to cultivated area, lack of soil fertility and humidity, so, plant products did not meet the requirements in both quantity and quality aspect. His Majesty has found the potential of the Vetiver grass that could be planted to conserve soil and water, lead to the solution of the mentioned problems. It was the propitious for Thai citizen that the royal thought along with His Majesty’s demonstration in applying Vetiver grass planting for soil and water conservation has been operated. By His Majesty’s prudential view and the practical methods, great inspiration and enthusiast among the citizen and government officers in every department were built up. The Royal thought about the Vetiver grass application for prevention of soil erosion has factually expanded to agricultural area from places to places. Planting of Vetiver grass results in farmers’ achievements for products enhancement, durability of the cultivated area and beautiful scenery of the residential area where the Vetiver grass will aid in soil and water conservation.

  The Project’s area in Khao Cha-ngum Deteriorated Land Rehabilitation Study Center by the Royal thought in Potharam district, Ratchaburi province was the model for schievements in Vetiver grass planting to solve degraded soil problems which the former was arid lateritic soil.

   Land Development Department is the major agency to operate soil rehabilitation by planting Vetiver grass in various styles such as to plant in row along the slope, up-side-down V-shaped style to solve deep gulley condition and for enhancement of soil fertility.

  The benefit of Vetiver grass utilization for degraded soil rehabilitation comes from the reason that the grass is one of Thailand’s native plants which has been disseminated and well adapted in various ecological conditions around Thailand and be able to grow in any kinds of soil, regardless of poorly fertile soil, acid-sulfate soil, acid soil, sandy soil, shallow soil, lateritic soil, gravel-mixed soil, deserted mine soil or salt-affected soil. However, primary plantation also requires special care until the tillers can set themselves, the process needs no charge but delicate care taking by watering and adding manure to maintain the soil.

   Vetiver grass function aids in reducing damages from water flush in rainy season, increasing soil humidity in arid season, acting as nursing crop for forestation and soil and water conservation in economic crops plantation. The Vetiver grass planting period and suitable styles should be considered for each problems target area. If the soil has been appropriately improved and humidity adjusted, the Vetiver grass will rapidly grow and become permanent compact fencing within short period of time. The dense culms above the soil surface will aid in soil sediment and organic matters filtration which are washed away by inundation, results in decreasing the movement of those matters, when there are sediment and the degradation takes place, the soil above the Vetiver grass fence will increase in fertility. Spreading of the grass root aid in better clinging and holding of the soil, results in better soil structure so that water can infiltrate through the depth of the soil along the Vetiver grass root, the degraded soil will be turned to earth dam for water conservation, so, the soil becomes humidified and appropriated for various kinds of plants. The Suitability for various environments in planting of Vetiver grass should be considered due to the planters’ requirements for the Vetiver grass to act as the soil and water conservation system and compares to the streak walls which protect the soil. 

 
   The utilization of Vetiver grass planting for soil and water conservation has been operated in various areas such as sloping land, high land, plain, lowland and water resource land by planting them in the soil erosion area prior to the crop plantation for prevention and after for rehabilitate the area. At present, we will find that the Land Development Department and various government and private agencies are planting Vetiver grass in the regular slope area by planting in continuous row style. If the bare root tillers are used, the spacing will be 5 cm and 10 cm for the bagged seeding of Vetiver grass. Each of the planting layers will be parallel by keeping the spacing for 1.5-3.0 m. The semicircular planting style could also be used with fruit plantation in irregular slope area. Other than that, the Vetiver grass planting also supplement the original soil and water mechanical conservation systems in bio-engineering style, for example, terracing, hillside ditch and farm road for long standing utilization. If the farmers have limited farming area, Vetiver grass should be planted along the farm edge and for highly soil erosion area, the planting should begin at the gulley and then extend to both sides of the mound.

   The great intelligence in methods information explanation of His Majesty to the citizen appear before royalty and to His Majesty’s followers to many areas result in the application of Vetiver grass in various ways. Being a plant belongs to the grass family, Vetiver grass has several special qualities, for example, Vetiver’s rhizome is embedded under the ground, so that it still can vegetate even burnt by the forest fire or grazed by animals, growing in single clump, not expand to disturb other plants, strong and dense fibrous root help keep water in soil, the root that can penetrate deeply in loose soil area effectively holds and strengthen the soil granule and the root inhabit useful microorganisms and micorhyza. Land Development Department has conducted Vetiver grass experimental planting by rowing up in steps vertically along the slope area and it has been concluded that Vetiver grass planting has successfully kept large quantity of soil sediment to the area and also enhance soil humidity results in rising in quantity of economic crop products. Vetiver grass, the appreciation for the royal grace

   The development operated in planting of Vetiver grass to solve erosion soil problems in various areas. The Land Development Department and other agencies are to fulfill the Royal thought by breeding Vetiver grass for dispensing to general farmers. Soil doctors from the Land Developing Department who have transfer ability will be the mainstay to educate and train farmers in the area. Soil doctor farmers planted Vetiver grass in their own land until being acceptable. The achievements brought about pride to the government officer team which has been working together in the development project and Vetiver grass planting by the Royal thought campaign. His Majesty’s royal duties and interests have been recognized and widely accepted by the farmers who have gained the benefits from Vetiver grass planting, the achievements are widely renowned.

   The area in the Northern part of Thailand consist of high slope mountain, the encouragement for farmers to conserve soil and water is very important because the area is the river source which being invaded for growing crops. Local agencies will operate in the area by acting as the center to give advice and systematize sloping land crop production. Vetiver grass has ability to adapt itself for growing in cold climate and to prevent soil erosion in high land and slope area, by planting Vetiver grass so that the farmers are able to grow economic crop such as vegetables, flowers, cold climate fruits then harvest the products for sale to earn household income. To plant quality Vetiver grass, the process should be done gradually, persistent care taking, maintaining, restoration and cooperation from resident farmers in the same river basin area are also needed.

   In the North Eastern part of Thailand which the majority of soil are sandy soil, gravel-mixed soil and lateritic soil, it was admirable for the farmers that they plant Vetiver grass instead of the field ridge, plant for maintaining farm road, for strengthen the pond edge, planting in the field crop area where they grow Cassava, sugar cane or peanut, in the orchard where mango or sweet tamarind are grown. 

 

   In the Central and Western part of Thailand, the operation was not easy to persuade farmers to agree for introducing Vetiver grass into their orchard area. However, by continually cooperative working between local volunteered soil doctors and Land Development Department officers, the demonstration fields in soil doctors’ residential area were established along with land consolidation project for various type of productions, Vetiver grass planting in reservoir farm pond area to maintain the land condition, utilization of the grass for mulching and applicable use for pesticide and chemical agent residues absorption.

   In the Southern part of Thailand, Vetiver grass is planted in rubber plantation area or orchard where the grass will help retain soil humidity and fertility. In some areas, the farmers have cooperated and produce Vetiver tillers for sale to other interested farmers; this is also an effective strategy to earn extra income for the household. Farmers who have succeeded in Vetiver planting would let other farmers to visit their plantation and they would instruct and explain Vetiver grass applicable use by themselves so that makes the spreading of the campaign to be faster. The development emphasize on the collaboration of people in the community, so everyone should give importance to Vetiver grass utilization in land development in variety of area types such as sloping area, river sources which were destroyed until becoming degenerated area, high land, plain, low land and the area outside cultivated area that have soil wash away and erosion problems. Various styles of Vetiver grass planting should be considered for planting in the mentioned degenerated area to help maintaining valuable topsoil and soil fertility Vetiver grass and Soil and Water Conservation

   Farming on sloping area or highland frequently causes soil erosion problem which impacts land resource and the environment, reduces soil fertility and crop products and also shallows rivers. The control and solution to soil erosion problem were to increase production cost, wasted expenses for operation and maintaining, the farmers rarely accepted because to acquire expected products, farming technique adjustment were needed in the way that to increase input factor and there was risky for not being cost-effective, so, they did not recognize direct benefits of the mentioned conservation system. There were simple conservation methods to be selected, which help for acquiring normal or higher yield of crop products and were operated by the farmers themselves including planting various plants and conservational management such as Contour Cultivation and Agroforestry that the plants were grown in row or bar fencing to entrap soil sediment and to prevent trees from being wash away. Plants that were grown for conservational fence were in grass family and legumes. Vetiver grass was one of the plants in grass family which could be used for the mentioned benefits. It is appeared to be that contour cultivation of Vetiver grass is the basic concept in Vetiver grass utilization for soil erosion problem control and prevention.

   By using the prepared propagated tillers for planting in the area, regularly, tillers in small plastic bags (2 x 6 inches), ageing 45-60 days or tillers from cultivated plots are used. Simple method in preparing shoots to be planted for prevention of soil erosion is, digging up the whole clump and cut off the root remaining 10 cm left and cut off the apex to leave the haulm for 20 cm long, separate the shoots then tie them up together into bundles the same as we do with rice seedlings. Immerse the root part in water for around 5-7 days, the new roots germinate then they will be planted.

  Planting in single row or double row horizontally along the sloping contour needs accurate alignment, but the equipment for alignment does not need to be a surveyor’s telescope because such equipment is expensive and to apply, training is required. In the fields, farmers can align the planting row by themselves and it does not cause a lot of expense.

 

   Even the Vetiver grass can tolerate grow in bad or infertile soil, but it would grow better if the soil has been adjusted by mixing them with compost or manure and spattering with fertilizer formula 15-15-15. Prepared Vetiver grass tillers in small plastic bags, ageing 45-60 days will be aligned in the planting furrow, creating 5-10 cm. spacing between each tiller, remove the bags undamaged so that the bags can be reused for tiller propagation, then burry the base tightly. If bare root tillers are used, 2-3 shoots per pit will be planted, with 5 cm. spacing between each shoots. 

   Vetiver grass tillers which are nursed in plastic bags grow and set itself faster than bare root tillers, but for sloping area in the North and South, bringing plastic bag tillers into the area can be inconvenient, sluggish and cost high expense, so, bare root tillers are still favorable. The optimal period for planting is at the beginning of Rainy season while the soil still has humidity, but for any areas that watering are possible, planting before Rainy season is preferable because when the rain comes, Vetiver grass fence will be able to filter out soil sediment and absorb overflow water, prevent soil erosion. Generally, it takes around three months for the tillers to set themselves and budding adjacent to each other to form a good Vetiver grass fence. 

   In high slope area condition, especially in the North and South where farmers like to grow perennial plants, the grass will be planted on the ridge of hillside ditch or bench terrace which are frequently collapsed when eroded by rain, especially right after the new construction has finished. To prevent damages as mentioned and to prolong maintain humidity to the soil, the simple method is to plant Vetiver grass at the ridge of the hillside ditch or the outer side of the ridge of bench terrace. 

   For the irregular gentle slope areas have fewer problems in soil loss due to rain inundation, planting Vetiver grass to keep humidity to soil can be operated by:

1. Circular planting around the tree, this method is used in the less or almost non slope area, especially the area lack of materials or plant residues for mulching. This method is useful for cutting off the grass leaves to cover the base of fruit trees to maintain soil humidity and to add organic matter to soil.

2. Semi-circular planting style, by planting the grass around 1.5-2.0 meters far from the base of trees in semi-circular alignment facing uphill to dampen the water flow and for soil sediment entrapment and confinement.

   The areas which are slope would be eroded and collapse easily by inundation, therefore, contour cultivation of Vetiver grass should be done to prevent water overflow and confine humidity to soil. In regular sloping area condition, the spacing between each clump is up to the area’s altitude. If the area is high slope, the spacing will be narrower than in low slope area, however, the spacing must not exceed 1.5 m in measuring horizontally which evaluated by transparent rubber tube level tool used by carpenter, so, it would be simple to do in orchard or perennial plant area in regular sloping. After marking the first row alignment, then the next row will be determined by row number of the tree, for example, the first row, there were 3 rows of the trees, so, every 3 rows there would be 1 row of Vetiver grass, however, for the grass to function effectively, the alignment of the fruit trees or perennial trees should also be contour cultivated (planted along the horizon across the sloping), too. And Vetiver grass planting between the trees row, spacing from the tree base will be 1.50 m, so the spacing measured vertically may be less than 1.50 meters or slightly greater than 1.50 m, appropriated for each tree row.

   In non slope or level area, there are no problems in soil loss, however, rain inundation can still occur, so, planting of Vetiver grass to keep humidity to the soil as much as possible appears to be a good method. Especially for the rainfed cropland, planting of Vetiver grass to confine water within the area by let the least water flow off the area, so, the grass will be planted in single row surrounding the area and the trees will also be surrounded by the grass, this is for utilized in cutting off the grass leaves for soil covering, lessen soil water loss.

   Planting Vetiver grass tillers along the edge of water source, the grasses will rapidly multiply their shoots tightly to each other to become row of dense and abiding Vetiver clumps. This will help filter out plant residues, soil sediment and other excretions from pouring into water source. Other than that, the amount of Vetiver roots are numerous, densely woven together forming underground wall, aid in holding soil together and chemical agents absorption before flowing into the water source, water from each water sources has good quality and is appropriated for consumption and also aquaculture.

   2.1 Water reservoir align Vetiver grass planting horizontally in to 3 rows.

          Row 1, plant at the overflow level or water confinement level.

          Row 2, plant at 20 cm vertically above the Row 1 and round the reservoir.

          Row 3, plant at 20 cm vertically below the Row 1 and round the reservoir.

   2.2  Ponds align Vetiver grass planting horizontally in to 2 rows.

          Row 1, plant at the pond edge, 50 cm from the pond rim.

          Row 2, at the pavement level.

   2.3 Canals waterways, watercourses, planting horizontally in row along the waterways
          or watercourses, 50 cm from the canal rim or river bank.After planting alignment has
          been set as desired, planting furrow are prepared alongthe line and mash the soil
          into fine grain. Adjust the soil along planting furrow by mixing the soil with compost
          then spatter with few amount of 15-15-15 formula fertilizer to make the grass grow
          and multiply its clumps better.

 
   Planting should be done in Rainy season while the soil is still moist, by placing Vetiver tillers in the prepared furrow in single row with 5-10 cm spacing, tightly burry the bases. After that, consistently care taking and replanting of died plants are needed. The grass leaves will be cut off and remain 40-50 cm tall after planting for 3 months, spatter few amount of 15-15-15 formula chemical fertilizer to accelerate faster clumping of the grasses into the row.

   Planting of Vetiver grass along the side of road shoulder is classified as one good method for preventing damages to road shoulder, especially non-asphalt road which frequently suffers from water erosion to damage and needs to be repaired. Alignment of Vetiver grass planting along road shoulder can be done by planting at the road shoulder side, the first row is on the road shoulder and the next row is around 50-100 cm. below, in order that, it is up to percent and length of the slope. The spacing between each clump is the same as the planting for prevention of soil erosion as mentioned above. Other than that, any climbing plants which hinder the Vetiver grass from growing should be prevented and eliminated. Planting methods are as the mentioned above, a single row of 5-10 cm. spacing of the tillers are planted. When the grasses multiply their clumps and tightly knit together, they will reduce erosion by rain and water, including the grass roots will nicely aid in holding road shoulder soil together.

   The other problem which frequently occurs is the erosion of road side sod waterway, in some places the drastic erosion may cause damages to roads, so Vetiver grass planting against waterway in the same style as planting to prevent deep gully erosion should be done in problem area in which the Vetiver fence will aid in problem solving nicely.

   Planting of Vetiver grass prevents garden bedding from erosion. Ridging of garden bedding which has deep gulley needs to be planted with Vetiver grass to prevent soil erosion by planting at least one row of the grass fence, 30 cm away from the edge of the bedding.

   Deep gully erosion problem in cultivated area can be solved by simple and economical method, especially the farmers can do by themselves. To solve the mentioned problem, Vetiver grasses are planted across deep gully, when the grasses fully grow, the clumps stand closely adjacent to each other blocking the gully, when water strikes the grass fence, it will be dispersed and flow through the gully slowly. Washed away soil sediment accumulates in front of the Vetiver grass fence, as the sediment piles up each year, there will be no problem to Vetiver grass growth because the grass is good at multiplying its clumps above the sediment, by this principle, soil will accumulate in the deep gully and finally fill it up. Another benefit achieved is, the Vetiver grass fences which are planted across the gully and along the slope in cultivated area will aid in water dispersion and water confinement to the farming area and also longer retain humidity in soil.

Species of Vetiver grass which are suitable for deep gully are Chrysopogon zizanioides Nash such as Sri Lanka, Songkhla 3, Kampaeng Phet 2, Surat Thani ecotypes and so on. The mentioned ecotype has tall clump, hard stem with nodes and erected leaves which these features can support water strike from inundation quite well and will always bud from the nodes when there are soil sediments piled up.

   Planting Vetiver grass across deep gully begins at the head of the gully which should be placed with stones or sandbags lining against the gully to reduce the strength of the tide. The first row of Vetiver grass will be planted behind the stone or sandbags lining and the next row will be planted far from the first row every 50 cm vertically, or in case of the strong tide, the space between each row may be 2 m horizontally. Both sides of the gully are usually very steep, upside down “V” shape of furrow (Ʌ) should be made for soil preparation, the apex of the “V” will be set in the middle of the gully and both arms of the “V” slope along both sides of the banks of the deep gully. Soil in deep gully erosion area is infertile, so, before planting Vetiver grass, small amount of formula 15-15-15 fertilizer should be spattered in the prepared furrow. The space between each tillers is 5-10 cm. and when the grasses age 3 months, the tip of the leaves will be cut off leaving the height for around 40-50 cm. to accelerate faster budding and welding of the clumps.

Planting Vetiver grass to retain humidity

   In general, to retain soil humidity in orchard, planting of Vetiver grass are likely to be done prior to plant any trees, but in case of trees have been grown before, planting Vetiver grass to retain soil humidity can also be done by planting in the row across the slope of the area between the canopy or align in semi-circular shape facing uphill to dampen water flow slightly outside the canopy. Planting Vetiver grass to retain soil humidity can be done in 

1. Planting in row between the trees or crops row. By planting 1 row of Vetiver grass every

     other 1-2 rows of trees and the space between the grasses is 5-10 cm through out the

     planting row.

2. Semi-circular style. By planting in semi-circular alignment 1.5-2.0 meters from the base
     of a tree with the concave side of the semi-circle faces uphill to dampen the inundation
     to retain water and soil sediment.

3.  Planting around the cultivated area. By planting Vetiver grass in rows around the
     cultivated area along the garden border, the space between the grasses is 5-10 cm.
     This will help retain soil humidity, increase amount of organic matters. Cutting off the
     leaves will also help for soil covering.

   Soil improvement in areas such as deserted shrimp farm and degraded area, Vetiver grasses should be planted all over the area needed, leaving spaces between each grass and each row by 50x50 cm, the same as in multiplication field. Soil preparation and care taking are the same procedure as in multiplication field. When the grasses age 2-3 years, they can be cut off, the leaves are used for ground covering and in case of the areas are needed for utilization, both the culms and the roots can be ploughed up and over, they will be decayed and become soil organic matters which aid in soil recondition suitable for growing plants and other economic crops.products.

   Generally, government agencies, farmers and general people can obtain Vetiver grass tillers and handbooks about planting and multiplication from Land Development Regional Office or Land Development Station nearby in government office hours as these offices have their own plant nurseries in the area. Other than that, people can obtain services from production and multiplication sources networks in sub-district level all over the country where there are learning center for sub-district stationed volunteer soil doctors.