Birches in the Woods (1930s)
Beech Tree (ca. 1936)
Blueberries in the Woods (1936)
Brassicaceae (1930s)
By the Stream, Krefeld (1939)
Campanula trachelium (1930s)
City Park, Cologne (1938)
City Park, Krefeld (1939)
Deciduous Forest, Krefeld (1939)
Deerpark, Cologne (1938)
Forest Path, Krefeld (1939)
Forest Stream, Puderbach/Westerwald (ca. 1930)
German Deciduous Forest, Krefeld (1939)
Group of Trees on the Hohes Venn during Calm (1930s)
Hieracium (1930s)