An Etymological Dictionary of the German Language/Lolch
Lolch, m., ‘darnel,’ from the equiv. MidHG. lulch, lullich, lulche, m.; the OHG. word is wanting, therefore it is difficult to determine when the term was borrowed from the equiv. Lat. lolîum. It is also conceivable that the G. word is independent of the Lat., especially as the former is lengthened by a guttural.