Changes in pasture and animal production resulting from the use of windbreaks

Abstract

The effect of windbreaks was studied in an experiment in which sheep were grazed continuously at 15, 30 and 37.5 ha-1 for five years. The paddocks were either square or rectangular in shape with fences of sheet iron or wire. In the square paddocks the sheet iron fences acted as a windbreak providing protection for plants and animals. In the first two years when rainfall was well below average, sheep in sheltered paddocks at 37.5 sheep ha-1 had marginally higher production than sheep in the other treatments, while at 15 sheep ha-L the productivity of the sheltered sheep was markedly higher. During the remaining three years, there were no large differences between treatments in herbage or animal production at the lowest stocking rate, while at the highest stocking rate sheep in sheltered paddocks had substantially higher production than those in unsheltered treatments. At 30 sheep ha-1 there was also increased plant and animal productivity from sheltered paddocks during the last two years of the experiment. This experiment is one of the first to show the effect of a windbreak on grazed pastures. The results indicate that shelter may have an important place in increasing pasture and animal production in the temperate areas of Australia.