''Chrysopogon nigritanus'', more widely known by the taxonomic synonym ''Vetiveria nigritana'', or the common name black vetivergrass, is a perennial
grass
Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns a ...
species of the family
Poaceae and therefore is also a
monocotyledon
Monocotyledons (), commonly referred to as monocots, (Lilianae ''sensu'' Chase & Reveal) are grass and grass-like flowering plants (angiosperms), the seeds of which typically contain only one embryonic leaf, or cotyledon. They constitute one of ...
.
[ Champagnant ''et al.'' (2007), p. 488.] More specifically, ''Vetiveria nigritana'' is a very thick and tall type of grass that is deeply rooted within the ground and is usually used to protect crops and deter
soil erosion.
''Vetiveria nigritana'' is also a native species to Africa and is most commonly seen in
Nigeria
Nigeria ( ), , ig, Naìjíríyà, yo, Nàìjíríà, pcm, Naijá , ff, Naajeeriya, kcg, Naijeriya officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf o ...
,
Northern Africa
North Africa, or Northern Africa is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region, and it is sometimes defined as stretching from the Atlantic shores of Mauritania in t ...
,
Eastern Africa
East Africa, Eastern Africa, or East of Africa, is the eastern subregion of the African continent. In the United Nations Statistics Division scheme of geographic regions, 10-11-(16*) territories make up Eastern Africa:
Due to the historica ...
and tropical parts of
Southern Africa
Southern Africa is the southernmost subregion of the African continent, south of the Congo and Tanzania. The physical location is the large part of Africa to the south of the extensive Congo River basin. Southern Africa is home to a number o ...
.
In addition, the plant, like other
vetiver
''Chrysopogon zizanioides'', commonly known as vetiver and khus, is a perennial bunchgrass of the family Poaceae.
Vetiver is most closely related to '' Sorghum'' but shares many morphological characteristics with other fragrant grasses, such a ...
grasses, has been used in these regions due to its extreme
drought tolerance
Drought tolerance is the ability to which a plant maintains its biomass production during arid or drought conditions. Some plants are naturally adapted to dry conditions'','' surviving with protection mechanisms such as desiccation tolerance, detox ...
, ability to grow in infertile soil and the fact that it can live under complete submergence.
[ Grimshaw (1994), p. 44.] In fact, ''Vetiveria nigritana'' can thrive in a very diverse range of environmental and climatic conditions.
''Vetiveria nigritana'' is a very beneficial plant within
subsistence agriculture, especially in Africa, due to its ability to preserve soils and reduce water runoff, which ultimately is correlated with higher crop yields. In addition, the plant is also beneficial in protecting a farmers stored crop harvests and plants while in the field because the plant can be used as a repellent or a means of destroying pest larvae before they have the ability to affect a farmer’s cash crop. ''Vetiveria nigritana'' also has various cost-effective medical applications for subsistence farmers and can be used as feed to maintain
livestock
Livestock are the domesticated animals raised in an agricultural setting to provide labor and produce diversified products for consumption such as meat, eggs, milk, fur, leather, and wool. The term is sometimes used to refer solely to animal ...
in the absence of other more common feeds.
Related species
''
Chrysopogon zizaniodes'' is a directly related species of the perennial type grass that has been more widely adopted by farmers, especially in India.
However, the two forms of vetiver grass are very similar in their benefits and growing conditions; the largest difference is that ''Chrysopogon zizaniodes'' has been more widely studied and used, especially to create
fragrance
An aroma compound, also known as an odorant, aroma, fragrance or flavoring, is a chemical compound that has a smell or odor. For an individual chemical or class of chemical compounds to impart a smell or fragrance, it must be sufficiently ...
s.
Soil erosion and runoff prevention
One of the main benefits of using ''Vetiveria nigritana'', especially in
subsistence agriculture, is that it reduces
soil erosion and nutrient loss associated with water
runoff
Runoff, run-off or RUNOFF may refer to:
* RUNOFF, the first computer text-formatting program
* Runoff or run-off, another name for bleed, printing that lies beyond the edges to which a printed sheet is trimmed
* Runoff or run-off, a stock marke ...
and wind displacement. Essentially, when ''Vetiveria nigritana'' is planted in hedgerows surrounding a crop or in multiple spaced rows, it creates a barrier that prevents soil run-off.
This is because the plant’s thick grass structure is able to accumulate soil and nutrients, such as
nitrogen
Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...
,
phosphorus
Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Ear ...
and
carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon mak ...
that would otherwise have been lost due to runoff. In fact, studies have shown that planting ''Vetiveria nigritana'' hedgerows reduces soil loss by around 70%, which allows farmers to retain the nutrients within their soil.
Secondly, the use of ''Vetiveria nigritana'' also reduces
water runoff
Water (chemical formula ) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living ...
, in some cases by 130%, which is beneficial because in areas where irrigation is not present, conserving natural rainfall is essential for the survival of a farmer’s crop.
In addition, the use of the type of vetiver grass is ideal in places like the African subtropics to prevent
soil erosion and runoff because ''Vetiveria nigritana'' has been shown to be highly effective on a variety of different slopes in preventing the degradation of soil.
Therefore, ''Vetiveria nigritana'' would benefit subsistence farmers because the increased nutrients, retention of soil and the accumulation of water that it causes would help to improve crop yields.
Pest control
Another benefit of ''Vetiveria nigritana'' is its ability to deter pests from damaging crops while in the field during the growing season and from ruining the quality of plants while in storage. In Africa it was discovered that by planting ''Vetiveria nigritana'' in hedgerows around
maize
Maize ( ; ''Zea mays'' subsp. ''mays'', from es, maíz after tnq, mahiz), also known as corn (North American and Australian English), is a cereal grain first domesticated by indigenous peoples in southern Mexico about 10,000 years ago. The ...
, that maize stem borers would attach to the plant more frequently than to maize and when the larvae hatched the potential borers died. In addition, ''Vetiveria nigritana'' is also beneficial in protecting certain crops after harvest, such as
rice
Rice is the seed of the grass species '' Oryza sativa'' (Asian rice) or less commonly ''Oryza glaberrima'' (African rice). The name wild rice is usually used for species of the genera '' Zizania'' and '' Porteresia'', both wild and domesticat ...
crops, because when the leaves of the plant are boiled in sea salt and then placed below and above the crop in a storage environment they act as a
repellent for insects, while also preventing mold.
Therefore, the use of ''Vetiveria nigritana'' would be beneficial to subsistence farmers because it would protect their crops and help ensure their survival.
Livestock protection
Additionally, ''Vetiveria nigritana'', like other forms of vetiver grasses, is beneficial in protecting the livestock of subsistence farmers. Even though vetiver grasses usually have a low protein ratio of about 8% they can be continuously harvested and fed to livestock if there is a shortage of other feeds for the animals due to poor harvests, diseased crops or contaminated storages.
[ Grimshaw (1994), p. 45.] This is valuable to subsistence farmers because a lack of feed usually leads to animals being slaughtered. Therefore, as a result of the use of vetiver grasses, the fertilizer production and grazing benefits of livestock are not lost, which is another reason why they are ideal for subsistence farmers.
Medical uses
There are many medical uses that have been derived from ''Vetiveria nigritana'' because the plant contains very high levels of
essential oils
An essential oil is a concentrated hydrophobic liquid containing volatile (easily evaporated at normal temperatures) chemical compounds from plants. Essential oils are also known as volatile oils, ethereal oils, aetheroleum, or simply as the o ...
that can be distilled and used for
traditional medical applications.
[ Champagnant ''et al.'' (2008), p. 68.] Firstly, ''Vetiveria nigritana'' can and has been used to increase the quality of the taste of drinking water in less developed nations such as Africa.
[ Chomchalow (2001), p. 12.] In addition, the plant has also traditionally been used to eliminate pathogenic bacteria that are present.
Lastly, ''Vetiveria nigritana'' is also beneficial at reducing diarrhea and has been used historically to treat children with a great deal of success.
Therefore, ''Vetiveria nigritana'' is beneficial to poor farmers because it provides traditional cost effective ways to fight infections and disease.
Increased crop yields
The use of ''Vetiveria nigritana'' is also valuable to farmers because it has directly been correlated with increased crops yields. Under certain forms of consistent cultivation, it was discovered that ''Vetiveria nigratana'' was beneficial in increasing
maize
Maize ( ; ''Zea mays'' subsp. ''mays'', from es, maíz after tnq, mahiz), also known as corn (North American and Australian English), is a cereal grain first domesticated by indigenous peoples in southern Mexico about 10,000 years ago. The ...
yields by 49.1% and
cassava
''Manihot esculenta'', commonly called cassava (), manioc, or yuca (among numerous regional names), is a woody shrub of the spurge family, Euphorbiaceae, native to South America. Although a perennial plant, cassava is extensively cultivated ...
yields by 3.2% when compared to fields that were not currently using the
agricultural practice in Nigeria.
[ Oshunsanya (2013), p. 121.] This increase in crop yield associated with the use of ''Vetiveria nigritana'' would be ideal for poor and subsistence farmers because it could potentially increase the profits and food available to them for survival. In addition, the heightened crop yields that are caused by ''Vetiveria nigritana'' are largely facilitated due to its ability to reduce soil erosion and runoff.
Additional practical information
There are two main ways that ''Vetiveria nigritana'' is commonly used in agriculture. Firstly, Vetiver Grass Strips (VGS) is a common form of ''Vetiveria nigritana'' use, which consists of hedge rowing vetiver grasses around a crop to reduce erosion, while still allowing for the cultivation benefits of spatial rowing.
[ Babalola ''et al.'' (2007), p. 7.] In addition, another common way to use ''Vetiveria nigritana'' that is beneficial to farmers is Vetiver Grass Mulch (VGM), which is a process of creating mulch out of the plant and then dispersing the residue over an area of farmland to decrease soil erosion and increase infiltration.
As for advice for the growth of ''Vetiveria nigritana'' and other vetiver grasses, they should be planted quickly in wet areas if the farm is accustomed to severe runoff or the plant should propagated in containers and then transplanted to these areas, to ensure initial survival.
In addition, the plants should be spaced six inches apart within hedgerows,
and intervals of 5 meters between the rows have been shown to be the most effective in soil retention.
[ Oshunsanya (2013), p. 124.]
Notes
References
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External links
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{{Taxonbar, from=Q15513123
Panicoideae
Plants described in 1917