BOTANICAL SCIENCE
RESTORE AND REWILD UNDERGOES A
RETHINK
NEW INSIGHTS INTO GENETIC VARIABILITY ARE HELPING TRANSFORM THE WAY WE APPROACH NEW PLANTINGS AND HABITAT RESTORATION. BRETT SUMMERELL REPORTS.
O
ver the summer period one rarely seen Australian became something of a media celebrity. In case you missed it, I’m talking about the pink flannel flower, Actinotus forsythii, which flowered in profusion throughout parts of the Blue Mountains, Southern Highlands and a little further afield. This species is what is known as a fire ephemeral, which means it requires bushfires followed by good rainfall for its seed to germinate, grow and then flower in masses. The past 12 months have of course delivered these conditions by the bucket-load, which is why we were treated to large areas covered by these wonderful pink flowers. This phenomenon highlights the amazing capacity of many species of plants to adapt to the diverse conditions they may face and their ability to wait – in some cases decades – until the right combination of environmental factors is provided. The capacity of species such as the fire ephemerals to cover large areas and reproduce prolifically is one of the wonders of nature and is an inspiring sight to experience. Despite this in-built resilience, the combined impacts of land-clearing, invasive species and climate change are pushing many plant species on the slippery path towards extinction. At a recent symposium on the fungal disease Myrtle Rust, for instance, plant scientists were presented with evidence of 16 rainforest trees that are faced with imminent extinction – and this only
11 years after the pathogen was introduced into Australia. While we are starting to recognise the need to restore and rewild the bush, there is still some debate how we best go about it, and how we ensure that our efforts take into account a changed and changing environment.
A PROVEN SOLUTION It’s clear that planting trees, restoring habitats and rewilding cleared bushland will all be important elements in our efforts to mitigate the impact of climate change. Trees have the capacity to store carbon in their trunks, moderate temperature and stabilise, at least to a certain extent, climate over large areas.
Tree planting is a proven solution that is also the most adaptable technique across socio-economic gradients. In addition, it is not restricted to rural communities – increased canopy density in urban areas helps reduce the ‘heat island effect’ and makes suburbs more liveable, particularly on days of intense heatwaves. Across many parts of the world, including Sydney, there are now strong government- and communityled programs to increase the number of tree plantings that occur and to make green infrastructure an essential component of new developments. The challenge is to ensure these plantings are sustainable.
Bioinformatic models are helping to optimise pollination
THE GARDENS WINTER 2021 19
