Himalayan Balsam

Impatiens glandulifera

This is not what it seems. It is certainly very beautiful. Even the seed pods are stunning. Sadly though it was introduced into the UK in the 1830's (clearly because of it's beauty) and is extremely invasive. The seed pods produce 800 seeds at a time, fired 7m away and more. Needless to say, it is destroying native plants. 

Yes its great for bees, yes it is very attractive along the river bank but, like some very lovely animals introduced to areas they don't belong, it is a huge problem. 

Pesky humans.......