Invasive Weeds Management
Himalayan Balsam. (HB)
Himalayan Balsam is an annual plant that reproduces from seed. As the seed pods ripen, they explode spreading the seeds for up to 7 meters.
Recommended methods of control.
1. Spraying using knapsack sprayer and systemic, glyphosate based herbicide. Roundup Pro Biactive is widely accepted as the most effective chemical suitable for use near watercourses. The main disadvantage to using herbicides to control any invasive weed is the unavoidable application to native plants growing in the immediate vicinity of the target species. Consequently, spraying is only recommended where HB forms large dense stands and prior to flowering.
2. Strimming and mowing of HB is effective but only prior to the seed pods developing. Any attempt to cut this plant once the seeds have developed will cause the seed pods to burst, spreading the plant. Strimming can be performed from spring to around early July.
3. Manual pulling. This is a slow technique only really suitable for low density infestations. Pulling should be performed prior to the formation of seed pods. The plant should be uprooted if possible as this ensures that new shoots can’t develop. This method is highly suited to dealing with initial outbreaks of the species.
As HB is an annual and its seed viability is thought to be around two years, it can be eradicated in a relatively short period of time with sufficient effort. Strategic control from the upstream limit would be required to achieve this goal.
