Sunday, October 14, 2007

Ferals along the River Bank

Feral plants can be beautiful despite causing damage to the local ecology. Along the riverbank the weeds are thriving between the tall eucalypts. An abundance of Lantana, Prickly Pear, Boganvillea, Mother-in-Laws Tongues, Asparagus Fern, grasses galore, Morning Glory, Camphor Laurel and many more flourishing even in the midst of drought. Some of these plants are escapees from suburban gardens; some may have been brought or planted by the people who used to live along the river in their small boats.

In his exciting book Feral Future (1999, 2001), the biologist Tim Low documents the litany of garden variety escapees along with many other feral species of plant, animal and insect which have decimated ecosystems in Australia and globally. While perfomer John Williamson sings 'The Cootamundra Wattle is my friend', Low writes that the Acacia baileyana 'has invaded woodlands to Africa, Europe, America, New Zealand and Australia' (2001:xx). He terms such feral plants 'invaders' - species that are out of place and once released, do great damage. The cause? 'Our collective ignorance' (2001:xxi).

The riverbank then is charged with a history of ignorance.

So which weeds grow where? And how can we find out what is, or is not a weed? The 2007 National Weeds Strategy defines weeds as: 'a plant that requires some form of action to reduce its harmful effects on the economy, the environment, human health and amenity.' Knowing this it is questionable why nurseries are still allowed to sell plants which may run rampant in the bush, like Agapanthus.

The document continues: 'Weeds are among the most significant and costly environmental threats in Australia. Of the 2700 species of introduced plants now established, 429 have been declared noxious or are under some form of legislative control in Australia. ... There are two types of invasion: introduction of exotic plants and movement by native species into new areas in response to changed land and water use and management practices.'

To combat the spread of exotic species, the government strategy recommends (among other actions): 'Prevention and early intervention are the most cost-effective techniques for managing weeds.'

In doing some internet research on Australian weeds, I discovered that just last week was the Australia-wide Weedbusters Week but there was no information about this important event that I saw in the local community, no advertisements on television, no broad community encouragement via posters in shopping centres, local organic stores or the small local nursery. Perhaps a group like Planet Ark should be given the responsibility for promoting such a national event, especially as the government's Weed Committee regards the problem as a such a significant issue.

The local bushcare group along the river is a small heroic group of weed baiters and tree planters intent on protecting this small patch of Brisbane riverbank from being completely overrun by weeds. This watchful group of river lovers is making a big difference.

Low T, 1999, 2001, Feral Future: The Untold Story of Australia's Exotic Invaders, Camberwell, Vic., Penguin Books.