The Danube's Delta is the area with the largest area with reed on Earth. The reed spreads across a surface of more than 170 000 ha.

The floating reed islets are a particularity of the reed area in the Danube's Delta. They are semi fixed. The floating reed islets are the perfect habitat for various species of plants, birds and even mammals. When these floating reed islets become too heavy, due to the vegetation growing on them, they sink and enter the Danube's Delta's natural circuit. The locals use the reed as fuel or as food for animals.

Before the 1990s, in Romania there used to exist factories which used reed as raw material. Today, half of the reed which grows in the Danube's Delta is harvested and exported to Germany, Italy or Holland, where it is used mainly for roofs.

The species presents variations, given by the biotope in which it develops. In the central part of the Danube's Delta grows the tall reed, with a height of 4 to 5 meters. On a surface of one square meter grow 40 to 60 stems of reed.

The lower waist reed, with a height of 1, 2 to 1, 8 m, can be found in the coastal area. In this area the density is larger, reaching 120 to 140 stems of reed per square meter. The reed acts as a filter for the waters which enter the delta and creates a propitious habitat for valuable species.