The Day of the Triffids re-created

Until a couple of years ago, I hadn’t realised how extensive the invasion of Himalayan Balsam had become along river banks. And then I went on a geo-caching adventure to an island in the middle of the River Tyne at Hexham and I saw the evidence with my own eyes as I hacked my way through head height plants.  Yesterday, a caching friend and I re-visited the island, taking the same route and indeed, adopting the same bush-whacking techniques.  The novelty soon wore off and I began to reflect on the urgent need to control this vigorous, flourishing immigrant plant!