What are shelter belts? What are their effects?

Question

What are shelter belts? What are their effects?

Answer 1

*A windbreak, or shelterbelt,

is usually made up of one or more rows of trees or shrubs planted in such a manner as to provide shelter from the wind and to prevent soil from erosion. They are commonly planted around the edges of fields on farms. If designed properly, windbreaks around a home can reduce the cost of heating and cooling and save energy. Windbreaks are also planted to help keep snow from drifting onto roadways and even yards. Other benefits include providing habitat for wildlife and in some regions the trees are harvested for lumber.

A further use for a shelterbelt is to screen a farm from a main road or motorway. This improves the farm landscape by reducing the visual incursion of the motorway, reducing noise from the traffic and providing a safe barrier between farm animals and the road.

*Shelter belts include planting trees to act as a wind barrier, which can:

reduce wind erosion of the soil

increase pasture growth by up to 60 % on exposed sites

increase crop yields by up to 25 %

increase stock weight gain by up to 34 %

increase milk production .

*Shelterbelt Layout



Shelterbelts will reduce the wind speed by 50 % on the leeward side over a distance equivalent to eight times the height of the shelterbelt on flat terrain. Shelterbelts should be placed at intervals of 6-10 times the height of each belt for maximum effect.

Plant at 4m intervals for farm shelterbelts.

Plant at 2-3 m intervals for horticulture shelterbelts.

Shelterbelts should be at 90 degrees to the prevailing wind.

Woodlots on suitable sites are more productive.

Bare stemmed species such as Eucalyptus can be supplemented with a second row of shrub species.

Planting along roadsides, streams or fence lines reduces pasture loss as a result of shading.

Shelterbelts For Hilly Terrain



When planting trees for shelterbelts on hilly terrain consider:

Planting smaller species on the lee slope.

Taller shelter should be concentrated on the more productive areas.

Locate shelterbelts near ridge crests where wind speeds are high but not on the crest to maintain landscape features.

Locate shelterbelts in saddles.

Scatter groups of trees in open areas to reduce exposure.