Invasive species coming our way – or already here!

We heard in our June meeting before the summer break of the problem with Himalayan Balsam growing on the banks of the Mimram and slowing the flow of water. But that is only one small threat to our environment; with the growth of the global economy we are being invaded!! In October, Martin Ketcher from the Herts and Middlesex Wildlife Trust, filled us with dread with more invasive species coming our way!

Of course, we have had non-native species in this country for a long time: those intrepid people who collected, and brought back, plants from all over the world. And some of these have become a big problem – think of the spread of the rhododendron. Often, unknowingly, one species was introduced to control another … rabbits in Australia? And, on my own doorstep, a pond plant, sold as a water oxygenater by garden centres has almost completely destroyed the pond in Woolmer Green.

Let’s think a bit more… Dutch elm disease wiped out our magnificent trees, box bush beetle is doing the same and what about ash die-back? And our penchant for world-wide travel means that we have packed bed bugs in our suitcases. I could go on and on but I’ll leave it to Martin Ketcher to fill in all those spaces. Of course, I don’t think we should be forgetting the traffic the other way; how many indigenous peoples have been decimated by the measles that we gave them?

Judith Watson


©2019 by Welwyn Natural History Society. Proudly created with

This site was designed with the
website builder. Create your website today.
Start Now