Garlic mustard research. Ecologist recording the position of garlic mustard (Alliaria petiolata) rosettes on a sheet of transparent mylar. The rosettes are clusters of green leaves low to the ground. The locations are recorded in June and October of the first year,and in June the following year,to enable estimates of rosette survival rates. The locations are converted into digital coordinates in a GIS (geographical information system) program,permitting spatial analysis. This plant,native to areas of Europe,Asia,and Africa,is an invasive plant in the forests of North America,where it can displace native plants. Photographed in Urbana,Illinois,USA |