Analysis of information sources in references of the Wikipedia article "Odontites vernus" in English language version.
Red bartsia (Odontites serotina) is a weed of hayland, pastures and roadsides which appeared in the Interlake region of Manitoba in the 1950s... The weed apparently was introduced into the area in crates which were shipped from West Germany into the Canadian Armed Forces Base at Gimli. The infestation started on the base and spread into surrounding farmland by way of mowed hay from red bartsia infested areas along the edges of runways.
