Impact of small balsam (impatiens parviflora) to plants of forest community

Impatiens parviflora is a species native to Asia. First it was recorded escaped from the Botanical garden in Drezden (1837) and later spread all over Europe. This species is an invasive plant in Lithuania because spreads rapidly and invades both semi-natural and natural habitats. Investigations on small balsam impact to plants of forest community were performed in 2005 in Verkiai regional park (Vilnius). During one vegetation season, coverage of plants and individuals of small balsam were registered in the test and control plots. These data let us to estimate relationships between plants of forest community and I. parviflora, speed and time of small balsam seed germination. Intensity of seed spread in autumn was investigated using seed catcher method. It was estimated that I. parviflora competes with I. noli-tangere, species of the same genus that is native in Lithuania. Strong facts, supporting hypothesis that small balsam competes with other native plant species were not found during this investigation