As plantations supply more of Australia’s timber, how they are established and harvested will increasingly shape biodiversity. Good management can make a substantial difference.

Native forest logging is winding back across Australia, so plantations will need to carry a growing share of the nation’s wood supply. Approximately one third of global timber is sourced from timber tree plantations, even though plantations cover only approximately 3 per cent of the area of forests globally. The primary objective of timber tree plantations is to grow forest products like timber and wood derivatives such as paper pulp and woodchips. However, plantations can sometimes have important values for biodiversity.

Understanding the potential value of plantations for biodiversity is important for several reasons. First, the global area of land used for plantations is large and increasing, having expanded by 75 per cent since 1990. In 2015, plantations covered 289 million ha of the earth’s surface – an area about 40 per cent the size of the entire Australian continent.

Second, plantations are often located in high-productivity areas which can also be important for biodiversity, such as for koalas (Phascolarctos cinereus) in parts of NSW and Victoria.

Third, the effects of plantations on biota can extend beyond areas directly under tree establishment and management to the broader landscape. For example, plantations can be a source of ‘wildlings’ that escape from plantation-managed areas, leading to invasive plant problems elsewhere.

Finally, plantations can alter key ecological and disturbance processes such as fire regimes and hydrological regimes, with subsequent impacts on biodiversity.

I recently led a major review of the factors which influence the value of plantations for biodiversity. The review was based not only on my experience from working in plantations in Australia since 1994,........

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