Grass, the ignored basis of much of Namibia's economy
Worldwide, grasses (Poaceae) in individual numbers exceed all other fa-milies of flowering plants, covering approximately 25% of the total vegetated land surface. They dominate the vegetation over great expanses of the earth and are exceedingly versatile in their adaptation to the environment.
Foods derived from members of the grass family, such as rice, maize, wheat, pearl millet, sugar - to name but a few - provide about 50% of all human calorie intake. Beer and spirits are brewed or distilled from the seeds of barley, wheat and maize. Other grasses serve as building materials [bamboo] or as thatching.
Grasses break the impact of rain drops on the soil and their dense root systems protect the soil from erosion. They provide co-ver for many small mammals, birds, reptiles and insects. Tall grasses even provide cover for stalking predators or sleeping lion.
Reportedly it has been found that grasses are even better at absorbing carbon dioxide from the atmosphere than trees. Grasses apparently store this gas in their roots, where it will not as easily be set free during a fire as when trees burn down.
Roughly 390 different grass species have been recorded for Namibia. They represent almost 10% of the total flora of the country. Grasses form the basis of two of the most important sectors of the Namibian economy, namely tourism and meat production. Of course, tourists do not eat grass, however, the large herds of ungulates they come to see in Etosha and elsewhere in the country could not exist without feeding on grasses that have adap-ted to the highly varied local conditions found in the country. In turn lion, leopard, cheetah and other carnivores indirectly depend upon a sufficient supply of grazing to support their prey animals.
As for agriculture, the staple grains produced in Namibia - maize and the northern pearl millet "mahangu" belong to the grass family. The Damara people of north-western Namibia collect certain grass seeds from the nests of the harvester ant and use it to make porridge or to brew beer. Dry mahangu stalks are often used as enclosures for the courtyards around traditional housing. The large numbers of beef cattle raised in the northern half of the country as well as many of the sheep produced in the southern parts also are entirely depen-dent on grass.
Annual grasses grow afresh from seed each season while perennial grasses survive seve-ral to many seasons. Perennial grasses propagate either by seeds or by sending out stolons above the ground or underground rhizomes to form new plants in the vicinity.
It is a unique feature of grasses that their leaves continue to grow throughout the life of the whole plant from a region at the leaf base. Grasses have evolved together with the herbivores of the savannas and to a certain extent their growth is stimulated by being grazed. However, continuous grazing and especially damage to the leaf bases will exhaust the plants and cause them to die. The same is true of frequent fires early in the dry season, which are often caused by negligence. Fires stimulate the grasses to sprout. But due to a subsequent lack of moisture the grasses exhaust their underground reserves and may die. On the other hand, fires shortly before the next rainy season are beneficial for they devour moribund grass tufts, which would otherwise choke new growth. These fires also stimulate new growth which will then be sustained by the rains.
After abundant rains in the past two seasons, the vast plains of southern Namibia and much of the Pro-Namib are covered in silky bushman grass (Stipagrostis uniplumis). 'Silky' refers to the shimmering light reflected from the silvery inflorescences of this grass, which is regarded as the single most important contributor to pasture production in Namibia. It is not confined to the southern half of the country but also occurs on sandy and stony soils all over the country.
The entire northern and north eastern regions of Namibia and the central high ground in particular have a much more varied grass cover than the southern parts, as can be seen on the photos.
Buffalo grass (Cenchrus ciliaris - Blaubüffelgras) is a wide-spread perennial climax grass, which quickly sprouts new leaves after the first rains. It is said to be as rich in proteins as lucerne, however, its palatability seems to vary for it is well-grazed in some areas and less so in others. Buffalo grass can be used as a cultivated pasture, but requires considerable amounts of fertiliser.
Wool grass, one of the most valuable and pa-latable grasses, also occurs wide-spread in Namibia and indicates good undisturbed veld and sound veld management, for it is one of the first species to disappear on over-grazed or otherwise disturbed land. It is regarded as the most valuable grass in the country and can be fairly easily recognised by its long grey to almost black flower spikes.
Sadly, there is not enough space in this paper to show more photos of the great variety of beautiful shapes in which grass flowers come. I can only encourage our readers to go for a walk in the veld a few weeks after good rains and to look for themselves. Collect some grasses - they make lovely dry arrangements.
For identification purposes, grasses may be divided into five groups according to the shape of their inflorescences. So look for unbranched spikes (Wool grass, Buffalo grass), digitate spikes, where more than one spike originates from a common base, spaced racemes where a few spikes are borne at irregular intervals on the central axis, contracted panicles which almost look like a spike but when bent can be seen to repeatedly branch and lastly panicles, which repeatedly branch and bear spikelets on secondary as well as tertiary axes (Red top, Silky bushman grass).
"Grasses of Namibia" by M.A. N. Müller, revised and updated by Johan van Eck and published by Ministry of Agriculture, Water and Forestry in 2007 [ISBN 0 86976 201] can be highly recommended to those taking a serious interest in grasses.
In this book grasses are also defined according to high, average of low grazing value, depending on their digestibility, nutrient content, the amount of dry material produced and their being perennial. Careful observation of the grass species in the veld gives a good indication of the veld condition. If perennial, palatable and nutritious grasses such as Wool grass are present in substantial quantities, the veld is in good condition. Certain other species indicate grazing in a transitional phase while large quantities of so-called pioneer grasses - the first grasses to re-appear on disturbed, overgrazed or eroded ground - indicate poor quality grazing.
While grasses are distributed all over the world, the only known true succulent grass in the world occurs in the coastal Namib between Lüderitz and Alexander Bay in the Northern Cape. Locally it is called "Kleinduimpiegras", which can be translated as "Tom Thumb grass". Succulence of course is an adaptation shown by many plants in this arid region and serves to store moisture, to prevent evaporation and to protect from sandblasting by the prevailing high winds.
So on your travels through Namibia, stop now and then and take a look at the grasses - not only do they play a very important role in reserving the soil, cleaning the air and feeding a large variety of animals - they are also very beautiful.
Foods derived from members of the grass family, such as rice, maize, wheat, pearl millet, sugar - to name but a few - provide about 50% of all human calorie intake. Beer and spirits are brewed or distilled from the seeds of barley, wheat and maize. Other grasses serve as building materials [bamboo] or as thatching.
Grasses break the impact of rain drops on the soil and their dense root systems protect the soil from erosion. They provide co-ver for many small mammals, birds, reptiles and insects. Tall grasses even provide cover for stalking predators or sleeping lion.
Reportedly it has been found that grasses are even better at absorbing carbon dioxide from the atmosphere than trees. Grasses apparently store this gas in their roots, where it will not as easily be set free during a fire as when trees burn down.
Roughly 390 different grass species have been recorded for Namibia. They represent almost 10% of the total flora of the country. Grasses form the basis of two of the most important sectors of the Namibian economy, namely tourism and meat production. Of course, tourists do not eat grass, however, the large herds of ungulates they come to see in Etosha and elsewhere in the country could not exist without feeding on grasses that have adap-ted to the highly varied local conditions found in the country. In turn lion, leopard, cheetah and other carnivores indirectly depend upon a sufficient supply of grazing to support their prey animals.
As for agriculture, the staple grains produced in Namibia - maize and the northern pearl millet "mahangu" belong to the grass family. The Damara people of north-western Namibia collect certain grass seeds from the nests of the harvester ant and use it to make porridge or to brew beer. Dry mahangu stalks are often used as enclosures for the courtyards around traditional housing. The large numbers of beef cattle raised in the northern half of the country as well as many of the sheep produced in the southern parts also are entirely depen-dent on grass.
Annual grasses grow afresh from seed each season while perennial grasses survive seve-ral to many seasons. Perennial grasses propagate either by seeds or by sending out stolons above the ground or underground rhizomes to form new plants in the vicinity.
It is a unique feature of grasses that their leaves continue to grow throughout the life of the whole plant from a region at the leaf base. Grasses have evolved together with the herbivores of the savannas and to a certain extent their growth is stimulated by being grazed. However, continuous grazing and especially damage to the leaf bases will exhaust the plants and cause them to die. The same is true of frequent fires early in the dry season, which are often caused by negligence. Fires stimulate the grasses to sprout. But due to a subsequent lack of moisture the grasses exhaust their underground reserves and may die. On the other hand, fires shortly before the next rainy season are beneficial for they devour moribund grass tufts, which would otherwise choke new growth. These fires also stimulate new growth which will then be sustained by the rains.
After abundant rains in the past two seasons, the vast plains of southern Namibia and much of the Pro-Namib are covered in silky bushman grass (Stipagrostis uniplumis). 'Silky' refers to the shimmering light reflected from the silvery inflorescences of this grass, which is regarded as the single most important contributor to pasture production in Namibia. It is not confined to the southern half of the country but also occurs on sandy and stony soils all over the country.
The entire northern and north eastern regions of Namibia and the central high ground in particular have a much more varied grass cover than the southern parts, as can be seen on the photos.
Buffalo grass (Cenchrus ciliaris - Blaubüffelgras) is a wide-spread perennial climax grass, which quickly sprouts new leaves after the first rains. It is said to be as rich in proteins as lucerne, however, its palatability seems to vary for it is well-grazed in some areas and less so in others. Buffalo grass can be used as a cultivated pasture, but requires considerable amounts of fertiliser.
Wool grass, one of the most valuable and pa-latable grasses, also occurs wide-spread in Namibia and indicates good undisturbed veld and sound veld management, for it is one of the first species to disappear on over-grazed or otherwise disturbed land. It is regarded as the most valuable grass in the country and can be fairly easily recognised by its long grey to almost black flower spikes.
Sadly, there is not enough space in this paper to show more photos of the great variety of beautiful shapes in which grass flowers come. I can only encourage our readers to go for a walk in the veld a few weeks after good rains and to look for themselves. Collect some grasses - they make lovely dry arrangements.
For identification purposes, grasses may be divided into five groups according to the shape of their inflorescences. So look for unbranched spikes (Wool grass, Buffalo grass), digitate spikes, where more than one spike originates from a common base, spaced racemes where a few spikes are borne at irregular intervals on the central axis, contracted panicles which almost look like a spike but when bent can be seen to repeatedly branch and lastly panicles, which repeatedly branch and bear spikelets on secondary as well as tertiary axes (Red top, Silky bushman grass).
"Grasses of Namibia" by M.A. N. Müller, revised and updated by Johan van Eck and published by Ministry of Agriculture, Water and Forestry in 2007 [ISBN 0 86976 201] can be highly recommended to those taking a serious interest in grasses.
In this book grasses are also defined according to high, average of low grazing value, depending on their digestibility, nutrient content, the amount of dry material produced and their being perennial. Careful observation of the grass species in the veld gives a good indication of the veld condition. If perennial, palatable and nutritious grasses such as Wool grass are present in substantial quantities, the veld is in good condition. Certain other species indicate grazing in a transitional phase while large quantities of so-called pioneer grasses - the first grasses to re-appear on disturbed, overgrazed or eroded ground - indicate poor quality grazing.
While grasses are distributed all over the world, the only known true succulent grass in the world occurs in the coastal Namib between Lüderitz and Alexander Bay in the Northern Cape. Locally it is called "Kleinduimpiegras", which can be translated as "Tom Thumb grass". Succulence of course is an adaptation shown by many plants in this arid region and serves to store moisture, to prevent evaporation and to protect from sandblasting by the prevailing high winds.
So on your travels through Namibia, stop now and then and take a look at the grasses - not only do they play a very important role in reserving the soil, cleaning the air and feeding a large variety of animals - they are also very beautiful.
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