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| 1. Grasses come in a vast range of sizes and types, ranging
from lawn grass to rice, wheat, corn, sugarcane and bamboo. |
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It is
estimated that there are about ten thousand different species of grass worldwide. They vary from short creeping lawn
grasses, to waist-high reeds and bamboo plants up to 40m (120 feet) tall. |
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| 2. Approximately 20% of the world's cover of vegetation has
grasses as its main ingredient. |
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Steppes,
prarie and savannah are ecological formations which all have grasses as one of their main
components. They cover vast areas of land. In Patagonia alone (South America), steppes
occupy an area 5 times the size of England. In Kazakhstan, Central Asia, steppes cover
27,800 square miles of land. These represent but small portions of the total
area covered. |
These grasslands are maintained by a complex mix of
interacting factors from soils and climate, to fire and grazing animals.
Few other habitats lack grasses of one type or another. |
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| 3. Hundreds of years old? |
| Some
perennial grasses clone themselves year after year, producing new shoots which are
genetically identical to those of preceding years. Individual plants of Red Fescue
(Festuca rubra) spread via underground stems known as rhizomes. A single plant has been
estimated to cover an area 250 metres in diameter. If the annual growth rate is measured,
the age of the individual plant can then be estimated. A plant of this size may be over
400 years old. |
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In clump-forming grasses, enormous clumps can also
eventually result. It has been estimated that a large plant of Sheep's Fescue (Festuca
ovina), 8 metres in diameter (equivalent to 4 men lying down, head to toe) might be 1000
years old! |
| 4. Grasses enabled cave
men to become farmers rather than hunters! |
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Grasses occur in
almost all parts of the world.
They produce seeds known as grains (for example, wheat, corn and rice). The grains
separate relatively easily from the parent plant and so can be collected.
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The
grains contain high proportions of nutritious oils and starches, making them a valuable
food both for humans and for their domesticated animals. The dry grains can be stored and used later,
providing food sources in winter when little else is available. They can also be sown in
the ground to germinate and produce new plants conveniently close to areas of habitation. |
Today, grasses
provide all of our cereal crops, the grazing for our domesticated cattle and sheep, as
well as most of the world's sugar.
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