Heather Angel / Himalayan balsam (Impatiens glandulifera), dissection of flowers. Male phase above, downward projecting stamens release pollen onto backs of bumblebees and honey bees. Female phase below with downward...

Heather Angel / Bumblebee (Bombus sp) nectaring on Himalayan balsam (Impatiens glandulifera). Surrey, England, UK. September.

Nick Upton / Himalayan balsam (Impatiens glandulifera) flower and seed pods close to bursting, Wiltshire, UK, September.

Adrian Davies / Himalayan Balsam (Impatiens glandulifera) seeds bursting from pod. Ripe seed pods do this in the wild when hit by rain drops. Digital composite.

Nick Upton / Eurasian beaver (Castor fiber) mother swimming and dragging a Himalayan balsam plant (Impatiens glandulifera) she has cut for her kits to feed on near their lodge, Devon, UK, July. Part of Devon Wildl...

Nick Upton / Young Eurasian beaver (Castor fiber) kit swimming , River Otter near its lodge with Himalayan balsam flowers (Impatiens glandulifera) reflected in the water around it, Devon, UK, July. Part of Devon W...

Cyril Ruoso / Himalayan Balsam (Impatiens glandulifera) an introduced species, Burgundy, France August

Cyril Ruoso / Himalayan Balsam (Impatiens glandulifera) an introduced species, Burgundy, France August

Gary K. Smith / Himalayan balsam (Impatiens glandulifera) flowers Cheshire, England UK. September. Invasive species.

Gary K. Smith / Himalayan balsam (Impatiens glandulifera) flowers Cheshire, England UK. September. Invasive species.

Philippe Clement / Himalayan balsam (Impatiens glandulifera) flowers, Belgium, August.

Nick Upton / Himalayan balsam (Impatiens glandulifera) flower close up, Cornwall, UK, June.