User:Kvonarx

Vorschau

Origin

 * here I will integrate the already existing stuff (Name, Systematics, Origin...)

===Morphology === The vetiver grass has a gregarious habit and lives in bunches. Shoots growing from the underground crown make the plant frost and fire resistant and allow it to survive heavy grazing pressure. The leaves can become up to 120-150 centimeters long and 0.8 centimeters wide. The panicles are 15-30 centimeters long and have whorled, 2.5-5.0 centimeters long branches. The spikelets are in pairs, and there are three stamens.

The plant stems are erect and stiff. They can persist deep water flow. Under clear water, the plant can survive up to 2 months.

The root system of vetiver is finely structured and very strong. It can grow 3-4 meters deep within the first year. Vetiver has no stolons nor rhizomes. Because of all these characteristics, the vetiver plant is highly drought tolerant and can help to protect soil against sheet erosion. In case of sediment deposition, new roots can grow out of burried nodes.

Usage
Vetiver grass is grown for many different purposes. The plant helps to stabilise soil and protects it against erosion, but it can also protect fields against pests and weeds. Vetiver has favourable qualities for animal feed. From the roots, oil is extracted and used for cosmetics and aromatherapy. Due to its fibrous properties, the plant can also be used for handicraft, ropes and else.

Erosion Control
Original entry is good, but some sentences can be added...
 * ... 2-4 meters, which is deeper than some tree roots.
 * ... rice paddies, and protects soil from sheet erosion. The roots bind to the soil, therefore it can not dislodge. The plant also penetrates and loosens compacted soils.

Water disaster mitigation
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 * The close-growing culms also help to block the runoff of surface water. It slows down flow velocity of water and thus increases the infiltration. It can withstand a flow velocity up to 5 meters per second.

Water conservation
Vetiver mulch increases water infiltration and reduces evaporation, thus protects soil moisture under hot and dry conditions. The mulch also protects against splash erosion.

Crop protection
Vetiver can be used for crop protection. It attracts pests such as the stem borer (Chilo partellus), which lay their eggs preferably on vetiver. Due to the hairy architecture of vetiver, the larvae can not move on the leaves, fall to the ground and die.

As a mulch, vetiver is used for weed control in coffee, cocoa and tea plantations. It builds a barrier in form of a thick mat. When the mulch breaks down, soil organic matter is built up and additional nutrients for crops become available.

Animal feed
The leaves of vetiver are a useful byproduct to feed cattle, goats, sheeps and horse. The nutritional content depends on season, growth stage and soil fertility. Under most climatic, nutritional values and yields are best if vetiver is cut every 1-3 months.

Other uses
Vetiver grass is used as roof thatch (it lasts longer than other materials), mud brick making for housing construction (such bricks have lower thermal conductivity), strings and ropes and ornamentals (the light purple flowers).

Crop Management
Vetiver is planted in long, neat rows across the slope for easy mechanical harvesting. The soil should be wet. Trenches are 15-20 centimeters deep. A modified seedling planter or mechanical transplanter can plant large numbers of vetiver slips in the nursery. Flowering and non-flowering varieties are used for cultivation. Sandy loam nursery beds ensure easy harvest and minimal damage to plant crowns and roots. Open space is recommended, because shading affects vetiver growth.

Overhead irrigation is recommended for the first few months after planting. More mature plants prefer flood irrigation. Weed control may be needed during establishment phase, by using 3 liter atrazine per hectare 3 days after planting.

To control termites which attack dead material, 1 kilogram of benzene hexachloride (BCH) can be applied for every 150 meter of the vetiver hedge. Brown spot seems to have no effect on vetiver growth. Black rust in India is vetiver-specific and does not cross-infect other plants. In China, stemborers (Chilo spp) have been recognised, but they seem to die once they get into the stems. Further, vetiver is affected by Didymella andropogonis on leaves, Didymosphaeria andropogonis on dead culms, Lulworthia medusa on culms and Ophiosphaerella herpotricha. Only in Malaysia white flies seem to be a problem. Pest management is done not only by using insecticides but also by appropriate cultural management: hedges are cut to 3 centimeters above ground in the end of the growing season. In general, vetiver is highly tolerant to herbicides and pesticides.

Harvest of mature plants is performed mechanically or manually. A machine uproots the mature stock 20-25 centimeters below ground. To avoid damaging the plant crown, a single blade bouldboard plough or a disc plough with special adjustment should be used.

Literature
mostly The Vetiver Network International