Report

Hundreds of thousands of hectares within the Avon catchment suffer from dryland salinity, a damaging phenomenon caused largely by rising groundwater tables that bring salt to the surface. If nothing is done it is expected that the area damaged by salinity will keep increasing. Farms, public land, roads and country towns all face increased damage, at significant cost to the local communities and the state as a whole.

It is generally recognised that strategic tree planting will help to reduce water logging and thus prevent or minimise dryland salinity in susceptible areas. Hundreds of farmers in the region have planted trees across sections of their farms. However while the environmental benefits of such tree planting may take years or even decades to fully manifest, the planting itself and the use of land for trees represent real short term costs to farmers, and act as a disincentive to planting on a larger scale.

The full environmental benefits of large-scale tree planting in the Avon catchment are not currently being realised. For the planting that does occur, mallee eucalypts are the favoured tree. If planted in rows or alleys they provide water management and environmental benefits while still enabling other farming activities between the rows. Also, once established, these trees may be harvested regularly. The trees coppice and so new growth takes place from the stumps after each harvest. If commercial uses can be found for the harvested biomass it is felt that the scale of planting will increase significantly, with attendant increase in the environmental benefits that the trees provide.