Or Euphorbia cyparissias - Zypressen-Wolfsmilch, one of the most ubiquituous spure species on the hot lands of Lobau; they paint them yellow in spring. (And yes, that lilac flower there is an orchid, Anacamptis morio again.)
My Photographic Diary - Text & Pictures (c) by Hermann Falkner, Vienna, Austria click pictures to enlarge - Bilder anklicken für Vollanzeige