Yellow flag iris or Iris pseudacorus

The yellow flag iris is a common waterplant that
can be found in marshes and other wet places. It is
easely recognized by its large bright yellow flowers.
If you find the Iris, then reed , purple loosestrive and
cattails are in the near.
The flower of the Yellow flag iris is special and the most
striking part are the large petals (3):

The flowers of the yellow flag iris are fertilized mainly by
bumblebees (honey bee and Bumble bee) and the hoverfly.
These insects are attracted by the honey that is produced
by the petals (5) and by collecting that honey the make
contact with the stamen (4). On the large bright yellow
petal-like sepals or falls on can find a brown spot or
beard, guiding the Bumble bee.

The yellow flag Iris most important way of reproduction
is the vegetative way, by using its short and thick rhizomes.
this will also fasten the process of hydrosere:
The pond will be invaded by emergent plants such as Phragmites (reed-grasses), Typha (cattail), and purple ,
loosestrive transforming the pond into the
Sedge-meadow stage.
In this way, a pond can be covered by Iris in some years.
These are the rhizomes of the Iris Germanica .