Vetiver hedges and sisal halt soil erosion, improve soil and water conservation
Practical Action
Plant food reach leaves through the
trunk and branches to make the
tree grow.
Leaves and branches
fall to the ground.
Fallen leaves and
branches form soil
humus.
Roots take up plant
food from the soil.
Humus assists growing
helpful bacteria which set
plant-food free in the soil.
But the most challenge is caused by bad farming practices. Harmful farming practices include
the following:
Indiscriminate bush-clearing by slashing, burning our using chemical or mechanical
methods strip the land bare and leave it highly susceptible to both water and wind
erosion.
The elimination of vegetative cover and litter has catastrophic effects on the protection
of the soil against the shock of rains and the strength of run-off water. The removal of
vegetation also prevents the building of organic matter and the improvement of the
structure and porosity of the soil. Weeds serve as canopies to protect the soil and aid soil
and water conservation, whereas indiscriminate removal of weeds unduly exposes the soil
to erosion.
Pre-planting tillage or cultivation also takes its toll. The making of ridges, heaps and
mounds on bare soil exposes the soil to serious erosion.
Over-grazing: This is also a serious factor. While natural and planted pastures can
provide adequate cover to the soil and protect it from erosion, over-grazing and over-
stocking of pastures result in the removal of vegetative cover and undue trampling of the
soil by livestock. Animals' trails and footpaths invariably become channels for gully
erosion.
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