EN
The main aim of this paper has been to assess natural values of the Janówek area (Wrocław) from the geobotanical point of view. The area is a valuable natural territory because a rich population of Salvinia natans (protected by law and vulnerable species VU category), consisting of about 1000 handsome specimens occurs here. There are also situated localities of some rare species in Lower Silesia, i.e. Cyperus fuscus (NT cat.), Kickxia elatine (NT), Sherardia arvensis (LC) and Euphorbia exigua (LC), and a borderland, fragmentarily developed form of Kickxietum spuriae association, a segetal weeds community of the Caucalidion lappulae alliance, as well as the area of ecological use Łacha Farna Old River-bed. Probably, within the Janówek area a rare butterfly species Euphydryas maturna L. appears and this is one of the only two localities in Poland. The western part of the investigated ground should be conserved as the Protected Landscape Area.