What is Himalayan Balsam?
Although introduces into the UK in the 1830’s Himalayan Balsam has now become what we would call a naturalised plant. It has become most prevalent on waste ground and river banks where vegetation is allowed to develop without control. It can tolerate low light levels and thus shades out other vegetation it quickly creates impoverished habitats by killing off other plants. If Himalayan Balsam isn’t quickly controlled it can quickly become a major problem.
Giant hogweed is a tall, cow parsley-like plant with thick bristly stems that are often purple-blotched. The flowers are white and held in umbels, (flat-topped clusters), with all the flowers in the umbel facing upwards. The flower heads can be as large as 60cm (2ft) across.
Why is it a problem?
Himalayan Balsam is very easily distributed. Each plant can produce up to 800 seeds and these are dispersed widely as the ripe seed pods shoot seeds for up to 7m. These seeds can then be transported by several means. Animals can collect them on their fur, humans on clothing and feet or they could move freely in water and be transported further downstream. This is a devastating plant to the environment if allowed to spread.