- Native to Himalayan region.
- Significant invasive plant in at least 15 European countries.
- Requires moist soils and grows along riparian areas, irrigation ditches, roadsides and in wetlands.
- Annual succulent herb that spreads through seed.
- Orchid like flowers are shades of pink through purple. Blooms from July to frost.
- Mature seed capsules explode when disturbed and eject seeds up to 5 meters away from parent plant. Produces up to 2500 seeds.
- High nectar production, decreases native plant pollination by bees.
Consequences of invasion
- Increases erosion in winter due to thick patches of die off and exposure of bare soil.
- Dominates native vegetation and diminishes conservation value.
- More research is required but observations indicate that there is a 50% reduction in pollinator visits to native plants when policemen’s helmet is present in large numbers.
Integrated Pest Management Options
- Best time to remove policeman’s helmet is late June to early August, when it is in flower.
- Best to avoid removal once seed pods are ripe, as they will release seeds and may increase the spread of this plant.
- Handpulling is an effective control method. All pulled plants should be bagged and brought to a landfill or place plants on a black tarp and left for several weeks to ensure plants are no longer viable. Plants that have been deemed non-vialable can be composted on site.