: Impatiens roylei
: Ornamental jewelweed, policeman's helmet, Touch-me-not
: Can be distinguished vegetatively from natives, which have alternate leaves. Sometimes referred to as "Indian
" or "Himalayan balsam
: Herbaceous annual, reaching 2 m (6.5 ft) in height; succulent.
: Opposite to whorled (at least some of them), stalked, egg-shaped to elliptic, sharply and closely saw-toothed; 6-15 cm long.
: Erect to ascending; often branched; glabrous; 2 m (6.5 ft) tall; purplish-tinged; 6-sided in cross-section.
: Purple, magenta, pink, blue or white in color; irregular, borne on elongated axillary peduncles, 3 sepals, pouched, with short recurved spur; blooms in summer.
Fruit and seeds
: Seed pod, elastically dehiscent, 1.5-2.5 cm long, many-seeded.
: Native to the Himalayas. Found in moist habitats including stream and riverbanks, ditches, meadows, swamps and floodplain forests.
: By abundant, explosive seed, which also spreads by water.
: Orange jewelweed (Impatiens capensis
) and Pale touch-me-not (Impatiens pallida
Monitoring and rapid response
: Hand-pulling, mowing or cutting; effectively controlled using any of several readily available general use herbicides.
: The information provided in this factsheet was gathered from the Michigan Natural Features Inventory and the University of British Columbia.
Individual species images that appear with a number in a black box are courtesy of the Bugwood.org network (http://www.invasive.org).Individual photo author credits may not be included due to the small display size of the images and subsequent difficulty of reading the provided text. All other images appear courtesy of Google (http://images.google.com).