An interesting article from ‘Per Square Mile’ via ‘Urban Choreography’.

“Invasive might not be as bad as some environmentalists think –  from Tim De Chant  @ Per Square Mile – hold on tight we might be blasted by the fanatics….

One of the scourges of our globalized economy is invasive species. In California, annual Mediterranean interlopers have upended the state’s once perennial grasslands. The Australian outback has been blanketed with prickly pear cacti from the American Southwest. And wattles from Down Under are a scourge in South Africa. But as widespread as invaders are, we’re only just beginning to understand how they move around the globe, establish themselves, and reshape the ecosystems they disturb.

A key unsettled debate is whether or not invasive plants change patterns of biodiversity. Some studies have found that biodiversity suffers when nonnative plants arrive and take over. Others have found the opposite, that new species add to the mix rather than deplete or homogenize it. Well, the authors of a new paper published today in Science say both answers are right. According to them, it’s all a matter of scale. “

While the examples described in these experiments have revealed interesting results in regards to the effect that invasive plants have on indigenous species, I am still not convinced.  There are too many invasive species that I have seen in Melbourne and Victoria that clearly dominate and overtake the indigenous plants.

The issue of what is invasive is also very dependant on the location.  For example, the species Leptospermum laevigatum (Coastal Tea-tree) is indigenous to the coastal areas of Frankston (Victoria, Australia).  However a few kilometres inland at the Royal Botanic Gardens, Cranbourne it is considered to be an invasive weed and dominates the indigenous Leptospemum myrsinoides (Heath Tea-tree).

Read more of the article here and let us know your thoughts on the indigenous vs weeds issue.