The City of Perth is planting 85,000 trees in rural Western Australiab near the township of Koorda as part of its ongoing initiatives to offset carbon emissions from vehicles using its parking stations.

The planting is the second of a four stage programme first launched in 2009 with the planting of 85,000 trees at Kojonup in the state’s south-west.

Perth City owns, operates and manages a commercial parking business CPP City of Perth Parking which caters for some 5.2 million customers per annum. Within the increasing public consciousness of global warming, the motor vehicle has been identifi ed as a signifi cant contributor to growing energy consumption and deleterious gas emissions.

Why 85,000 trees?

While not an exact science, the basic assumptions used to calculate the carbon dioxide equivalents (CO2e) and thus the number of trees are as follows. A modern medium sized family car emits 0.2 kilograms of CO2e per kilometre travelled. On the basis of 5.2 million trips of 15 kilometres, (an average home-city journey) 15,600 tonnes of CO2e will be generated. To sequest 15,600 tonnes of CO2e a total of 85,000 trees will need to be planted and maintained to maturity.

In addition to the gas emission off-sets, there are a number of other benefi ts that are realised from the program:

1. The carbon rights generated from the tree planting are legally contracted to the ownership of the City, these rights are a saleable commodity.
2. The oil mallee tree being planted, is suitable for harvest and the generation of biofuels as a low emission alternative to fossil fuels. Mallee trees coppice (regrow from the root system) so that the carbon off-set capability is re-established.
3. The City’s ownership rights are protected by holding a covenant on the Land Title. Koorda plantings are on marginal agricultural land which will be enhanced as a result  of the project.
4. Having the City of Perth as the state capital invest in the rural areas outside the city recognises city/country relationships and their interdependencies.