impatiens glandulifera himalayan balsam invasive bloom flower blossom, expansive species dangerous plants asia neophyte

impatiens glandulifera himalayan balsam bloom invasive ornamental jewelweed flowers kiss mountain blossom expansive leaf species pink purple touching dangerous himalayas plants leaves fruits intruder sachalinensis achenes saw neophyte asia reduces green wild rhizome wildflower collect honey biodiversity eliminates gatecrasher contamination herbicides mechanically flower europe bushes calamity disaster large biomass insect