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Windbreaks Afrikaans | Xhosa

Click to enlarge!		 Large parts of South Africa are exposed to hot, dry winds in summer and very cold winds in winter. Therefore the provision of windbreaks to protect stock, agricultural crops and houses against the strong winds is essential.

A windbreak is a barrier placed in the path of the wind to "bend" its flow upwards. Trees make the most effective windbreak because they grow tall, they are long lasting and the space between them can be adapted. When the wind blows against the windbreak, some of the air passes through the branches and leaves, while the strongest part of the flow bends upwards and blows over the treetops.

The value of a windbreak:

  • The wind speed is considerably lessened with the result that the physical damage to flowers, fruit and plants, caused by hail, snow and sand, is decreased or even prevented. The quality and size of crops are therefore improved.
  • A lower wind speed offers greater protection to animals. Animals are less exposed to heat and cold, and losses as a result of deaths and decreased production are lower.
  • If a double row of trees is planted as a windbreak, one of the rows can in time be used for saw-timber, poles or firewood.
  • Windbreaks definitely increase the value and improve the appearance of a property.

Click to enlarge!		 How to plant an effective windbreak

Ensure that the trees are not planted too closely to each other. An effective windbreak allows 50 % of the wind to pass through the leaves and branches.

The density of the windbreak can be determined by the species of trees planted, the number of rows planted and the distance between the trees in the rows as well as that between the rows.

Click to enlarge!		 The windbreak must be at least twice as tall as the agricultural crops that are to be protected.

A windbreak offers protection over a distance of approximately ten times the height of the trees. If the windbreak has a height of 20 m, for example, it can protect a crop for a distance of 200 m. Such windbreaks must therefore be planted at intervals of 200 m.

Click to enlarge!		 Large gaps in a windbreak cause the wind to blow through them at high speed, to damage the crops behind the windbreaks.

Under certain conditions there are some tree species that offer greater advantages than others. In the cold areas where frost occurs, deciduous trees are more advantageous than evergreens. Because deciduous trees lose their leaves in winter, they allow greater air movement through the branches, with the result that there is less frost.

For maximum effect, the windbreak must be planted at rectangles to the wind that causes the damage.

S Steyn
ELSENBURG / WESTERN CAPE forestry extension