Amerikaanse Cyperaceae in Son en Breugel

Carex scoparia, Eleocharis engelmannii, Scirpus cyperinus, and S. georgianus, four Cyperaceae species from North America, were found in a water storage facility in the Sonniuspark, a new residential area in the municipality of Son en Breugel ( Province of Noord-Brabant, the Netherlands). In addition to these four North American species, a few other vascular plant species with possibly a North American origin grow or grew there as well. The water storage facility was constructed in 2010 for the development of this new residential area and was completed without sowing. A few hypotheses about the introduction of the species are discussed and, finally, one of these is considered the most plausible. The North American and possibly North Amercan species are not commercially available and the gardens in the area are too young for excess garden waste, which argues against the introduction of the species by the depostion of garden waste. The deliberate sowing or planting of the species by a private person is very unlikely, because the perpetrator must have been a great lover as well as a specialist of grassy monocotyledons. Such persons are rare. The most plausible hypothesis is that the introduction of these North American species is connected with Operation Market Garden in 1944. This military operation in World War II started in Son with the landing of mainly American troops: paratroopers and gliders with personnel and equipment. It is plausible that seeds were buried in the soil, particularly during activities related to collecting the gliders, and surfaced again with the construction of the water storage facility.