The on-farm productivity benefits of shelterbelts
SHELTERBELTS on-farm can increase pasture yields by 20 to 30 per cent and deliver up to 20 per cent increases in liveweight gains.
That’s in addition to halving lamb mortality and delivering a boost of up to 25 per cent in crop yields.
And these benefits mean that 10-30 per cent of a farm can be under native vegetation without affecting production.
This was some of the information shared with a group of farmers in South East South Australia recently as part of a workshop about soil health and shelterbelts.
Hosted by the Limestone Coast Landscape Board, this workshop was also told that local farmers and landholders believe shelterbelts – vegetative barriers in paddocks used to reduce wind speed – not only protect livestock and crops, they also add value to their properties.
A windbreak of cottonwood trees in western Colorado
This finding came from a survey used to underpin future local shelterbelt research and extension work.
The benefits above were applicable for the land – or microclimate – into the paddock as far as ten-times the height of the tallest trees in the shelterbelt.
Shelterbelts break wind speed but allow “cushions” of air to flow through to the area on the leeward side – the side away from the wind.
For those looking to build shelterbelts it was recommended that they investigate planting local species and plant a minimum of three rows of trees and shrubs – for a total shelterbelt width of 20 to 30 metres.
Shrubs were recommended for the outside of the shelterbelt – they fill in the gaps beneath the taller trees in the middle of the plantation.
In addition to delivering on-farm productivity benefits, shelterbelts can also provide a safe haven for local birds and other wildlife, especially if the vegetation is close to existing trees and shrubs.