GRASS COVER The global impact of
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t seems logical to establish vegetative cover on critical bare areas, and grass is the only cost-effective solution. Approximately 650 genera and 10000 species populate the earth - sparingly in waste, forest-covered and barren lands but densely in open savannahs, mountain sides, fields, roadsides and reclaimed land. In fact grass growth thrives everywhere on the earth's surface with the exceptions of the areas at the poles under ice. Grass species have hybridised naturally and within species there are distinct variants that have adapted to chalk land, high altitudes, sand dunes, shallow rocky soils, arable land and the water’s edge. In addition, there are interspecific hybrids of which Agrostis and Festuca play a major role in the establishment of sporting surfaces
The true value of grass
If we pause to consider the value of grass cover, its benefits are so numerous that they highlight the disastrous impact that would arise from destroying it.
• Grass seed is plentiful in most soils
• It stabilises the soil on natural and disturbed land
• It controls dust and binds the soil surface
• It restores organic matter after arable cropping
• It cools the soil surface and reduces extremes in ground temperatures
• It provides a vital link in nature’s ecosystems
• It gives pleasure in enhancing the value of our homes, cities and the countryside
• It provides an acceptable surface for relaxation and sport
• It acts as a buffer against wind and water erosion
Much has been written on grass. ‘Grass is the forgiveness of nature’, it can be abused and trampled, it can be removed and replaced, yet it is immortal and in its own time it always returns to resume its role in covering the earth.
Stabilising critical areas
On steeper gradients and rocky terrain there is difficulty in gaining access with mechanical equipment. In these instances hydroseeding is a viable solution. It involves spraying the seed in the fluid organic mulch and this is achieved from an agitated tank with pumping equipment capable of reaching distances in excess of 20 metres. Where ground is particularly unstable the earthworks design is vital and reinforcement or the use of rock-filled gabions must be considered. The surface of steep slopes exposed to high rainfall intensity or persistent dry conditions can make establishment difficult. The use of straw and organic mulches offers good protection and water retention during the period of germination and establishment. In addition, the use of geotextiles and biodegradable matting provide a means of stabilising and securing growth. The placement of grass turf specifically lifted from a grass nursery and pegged in position also provides an instant means of stabilising the soil where immediate
protection is required. In addition to the bulk
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